【宝山大华】2017年徐汇区西南模范中学初三3月月考卷
上海西南模范中学初三初三化学上册期中模拟试题(含答案)
上海西南模范中学初三化学上册期中模拟试题(含答案)一、选择题（培优题较难）1．质量相等的两份固体，然后分别放在酒精灯上均匀受热，放出氧气的质量(m)随反应时间(t)变化的函数图像(如图，a为纯净的氯酸钾，b为加入了高锰酸钾的氯酸钾)，正确的是( )A．B．C．D．2．中华传统文化博大精深。
下列古诗中不涉及．．．化学变化的是（）A．日照香炉生紫烟，遥看瀑布挂前川B．爆竹声中一岁除，春风送暖入屠苏C．粉身碎骨浑不怕，要留清白在人间D．春蚕到死丝方尽，蜡炬成灰泪始干3．锌是促进人体生长发育的必须微量元素。
下图为锌元素在元素周期表中的相关信息及原子结构示意图。
下列说法正确的是（）A．锌属于非金属元素B．锌原子的中子数为30C．锌的相对原子质量为65.38g D．锌原子在化学反应中易失去电子形成Zn2+ 4．下列有关实验操作的“先”与“后”的说法中，正确的是（）A．制取气体时，先装药品，后检查装置的气密性B．用托盘天平称量10g固体药品时，先放砝码，后放药品C．用滴管取细口瓶内的液体时，先将其伸入液体内，后挤压取液D．加热KMnO4并用排水法收集O2的实验结束时，先熄灭酒精灯，后移出导管5．下列是几种粒子的结构示意图，有关它们的叙述，你认为正确的是A．②表示的是阴离子B．①②③④表示的是四种不同元素C．③属于金属元素D．①③所表示的粒子化学性质相似6．用下图装置进行实验。
下列现象能证明空气中O2的含量的是（）A．红磷燃烧，产生白烟B．瓶中液面先下降，后上升C．瓶中液面最终上升至1处D．水槽中液面下降7．下列关于CO2的实验室制法及性质实验的说法不正确的是（）A、制CO2的药品B、发生装置C、收集装置D、比较CO2与空气的密度A．A B．B C．C D．D 8．河水净化的主要步骤如下图所示。
有关说法错误的是A．步骤Ⅰ可出去难溶性杂质B．X试剂可以是活性炭C．步骤Ⅲ可杀菌．消毒D．净化后的水是纯净物9．硼是作物生长必需的微量营养元素，硼元素的相关信息如图所示。
上海名校英语--2017学年上海市徐汇区西南模范九年级上学期周测试卷
Part 2 Phonetics, Grammar and Vocabulary（第二部分语音、语法和词汇）I．Choose the best answer（选择最恰当的答案）26. Which of the following underlined parts is different in pronunciation from others?A. He washed his hands.B. They stopped us from coming inC I walked home last night.D.Louise opened a bottle of wine答案：DA.[wɔʃt].B.[stɒpt]C. [wɔːkt] D ['əʊpənd]27. It's wrong you to leave the washing machineA. for... funB. of. runningC for. runningD. of. run答案：B，It’s +adj+of sb,其中adj为形容人时用of,不能用for，leave sth doing28. You will be out of date you keep on studying from time to time.A ifB, unlessC becauseD.Or答案:B,根据句意，你将会过时，除非你有时保持学习，选unless29.Don’t you think travelling by train is and far ?A more quickly .. more easilyB more quickly.. easierC．quicker, easlierD.quicker, more easily答案：C，根据far可知用比较级，用副词easily的比较级，前面是is，所以用adj,用quick的比较级30. He supposed that keeping pet dogs wasn't a good idea, ?A. was itB wasn’t itC. did heD. didn't he答案：D，宾语从句的反义疑问句，当主语是第三人称时，反主句，所以用did，在根据前否后肯，所以用didn’t he?31)I would rather at than give up this precious opportunity.A be laughedB laughC to laughD to be laughed答案：A,would rather do 的用法，排除CD，根据句意应用被动语态，与放弃珍贵的机会相比，我宁被嘲笑32.She’s announced that she her third chain store in a monthA had openedB would openC openedD. will open答案：D，由in a month ,可知用将来时，选D，她已经宣布她在一个月之后将开立她的第三家连锁店33. He watched the patient through the windowA closely, closeB close, closedC closely, closedD. close, closing答案：C，根据词性判断第一个空是adv，第二个是adj，他通过这个关着的窗户近近地看着这个病人34.The teacher asked us not to do the experiments by ourselvesA.physics, physicsB. physics, physicalC. physical, physicalD physical, physics.答案：B，学科老师的表达方法是学科直接加老师，所以第一个是physics，第二个空缺adj，所以用physical35. The light suddenly after the storm.A. went outB.went offC .went onD. went over答案：A，根据句意，这个灯突然熄灭了，在这场风暴以后，go out 是熄灭，go off 是爆炸，go on 是继续，go over 是复习36. When she came several days later, sfe found that all things still where shehad them.A. lay: laidB. laid: laidC lay: lainD. lying: lain答案A，find sb do ,所以第一个空用平躺的原型lay，第二个空她已经放的地方，用放置的过分laid，当她几天以后回来以后，她发现所有的东西还躺在他已经放的地方.37. A poet and artist coming to speak to us about Chinese literature and painting tomorrow afternoonA.isB. AreC.wasD, were答案：A，主语a poet and artist,指的是一个人，一个诗人兼艺术家，所以谓语动词是三单，主语而不是a poet and an artist.38. Helen her keys in the office so she had to wait until her husband homeA. has left; comes B, left; had comeC had left: cameD had left: would come答案：C，根据句意第一个空用完成时，后句有个had to ,所以用过去式，所以第一个空是过完，第二个空是came39. We’re to listen to her voice. It's to hear her sing.A. pleased; pleasant; a pleasureB pleasing; pleasant; pleasureC pleased; pleasing; pleasureD pleasing; pleased; a pleasure答案：A，根据词性判断前两个空是adj，前者修饰人用pleased,后者用来修饰物，所以用pleasant,第三个空用名词，It is a pleasure to do sth40. Under a big tree , half asleepA did sat a fat manB a fat man satC.did a fat man satD.sat a fat man答案：D，根据句意，在一个大树下，坐着一个胖人，快睡着了41. He slipped and broke his arm . ,he will have to be away from school for two or three monthsA. In any caseB.After allC As a resultD. In this way答案：C，根据句意，他滑到了摔坏了胳膊，所以，他必须休学2-3个月，A是在任何情况下，B是毕竟，C是所以，D，是用这种方法。
上海西南模范中学初三数学九年级上册期末模拟试题(含答案)
上海西南模范中学初三数学九年级上册期末模拟试题(含答案)一、选择题1．在半径为3cm 的⊙O 中，若弦AB ＝32，则弦AB 所对的圆周角的度数为（ ） A ．30° B ．45° C ．30°或150° D ．45°或135° 2．下列关于x 的一元二次方程，有两个不相等的实数根的方程的是( ) A ．x 2＋1＝0B ．x 2＋2x ＋1＝0C ．x 2＋2x ＋3＝0D ．x 2＋2x －3＝03．如图，矩形ABCD 中，3AB =，8BC =，点P 为矩形内一动点，且满足PBC PCD ∠=∠，则线段PD 的最小值为（ ）A ．5B ．1C ．2D ．34．若关于x 的方程 ()2m 110x mx -+-= 是一元二次方程，则m 的取值范围是（ ） A ．m 1≠.B ．m 1=.C ．m 1≥D ． m 0≠.5．已知Rt △ABC 中，∠C=900，AC=2，BC=3，则下列各式中，正确的是（ ）A ．2sin 3B =； B ．2cos 3B =；C ．2tan 3B =； D ．以上都不对；6．函数y=(x+1)2-2的最小值是（ ）A ．1B ．－1C ．2D ．－27．把二次函数y =2x 2的图象向右平移3个单位，再向上平移2个单位后的函数关系式是（ ）A ．22(3)2y x =-+B ．22(3)2y x =++C ．22(3)?2y x =-D ．22(3)?2y x =+8．若关于x 的方程20ax bx c ++=的解为11x =-，23x =，则方程2(1)(1)0a x b x c -+-+=的解为（ ）A ．120,2x x ==B ．122,4x x =-=C ．120,4x x ==D ．122,2x x =-= 9．已知⊙O 的直径为4，点O 到直线l 的距离为2，则直线l 与⊙O 的位置关系是 A ．相交 B ．相切 C ．相离 D ．无法判断 10．一组数据0、－1、3、2、1的极差是（ ）A ．4B ．3C ．2D ．111．某同学在解关于x 的方程ax 2+bx +c ＝0时，只抄对了a ＝1，b ＝﹣8，解出其中一个根是x ＝﹣1．他核对时发现所抄的c 是原方程的c 的相反数，则原方程的根的情况是（ ）A ．有两个不相等的实数根B ．有两个相等的实数根C ．有一个根是x ＝1D ．不存在实数根12．下列对于二次函数y＝﹣x2+x图象的描述中，正确的是（）A．开口向上B．对称轴是y轴C．有最低点D．在对称轴右侧的部分从左往右是下降的13．如图，点P（x，y）（x＞0）是反比例函数y=kx（k＞0）的图象上的一个动点，以点P为圆心，OP为半径的圆与x轴的正半轴交于点A，若△OPA的面积为S，则当x增大时，S的变化情况是（）A．S的值增大B．S的值减小C．S的值先增大，后减小D．S的值不变14．如图，点A，B，C，D的坐标分别是（1，7），（1，1），（4，1），（6，1），以C，D，E为顶点的三角形与△ABC相似，则点E的坐标不可能是A．（6，0）B．（6，3）C．（6，5）D．（4，2）15．二次函数y=ax2+bx+c（a≠0）的图象如图，给出下列四个结论：①4ac﹣b2＜0；②4a+c＜2b；③3b+2c＜0；④m（am+b）+b＜a（m≠﹣1），其中正确结论的个数是（）A．4个B．3个C．2个D．1个二、填空题16．如图，△ABC中，D、E分别在AB、AC上，DE∥BC，AD：AB=1：3，则△ADE与△ABC 的面积之比为______．17．如图，在半径为3的⊙O 中，直径AB 与弦CD 相交于点E ，连接AC ，BD ．若AC ＝2，则cosD ＝________.18．如图是一个可以自由转动的转盘，转盘分成6个大小相同的扇形，颜色分为红、绿、黄三种颜色．指针的位置固定，转动的转盘停止后，其中的某个扇形会恰好停在指针所指的位置（指针指向两个扇形的交线时，当作指向右边的扇形）．转动一次转盘后，指针指向_____颜色的可能性大．19．如图，已知Rt ABC ∆中，90ACB ∠=︒，8AC =，6BC =，将ABC ∆绕点C 顺时针旋转得到MCN ∆，点D 、E 分别为AB 、MN 的中点，若点E 刚好落在边BC 上，则sin DEC ∠=______.20．若a b b -＝23，则ab的值为________． 21．二次函数y=x 2−4x+5的图象的顶点坐标为 ．22．若点C 是线段AB 的黄金分割点且AC ＞BC ，则AC ＝_____AB （用含无理数式子表示）．23．如图，在ABC 中，62BC =，45C ∠=︒，2AB AC =，则AC 的长为________．24．二次函数2y ax bx c =++的图像开口方向向上，则a ______0.(用“=、>、<”填空)25．一种药品经过两次降价，药价从每盒80元下调至45元，平均每次降价的百分率是__．26．“上升数”是一个数中右边数字比左边数字大的自然数（如：34，568，2469等）．任取一个两位数，是“上升数”的概率是_________ ．27．如图，在边长为 6 的等边△ABC 中，D 为 AC 上一点，AD=2，P 为 BD 上一点，连接 CP ，以 CP 为 边，在 PC 的右侧作等边△CPQ ，连接 AQ 交 BD 延长线于 E ，当△CPQ 面积最小时，QE=____________．28．设1x 、2x 是关于x 的方程2350x x +-=的两个根，则1212x x x x +-•=__________．29．设二次函数y ＝x 2﹣2x ﹣3与x 轴的交点为A ，B ，其顶点坐标为C ，则△ABC 的面积为_____．30．如图，在△ABC 中，P 是AB 边上的点，请补充一个条件，使△ACP ∽△ABC ，这个条件可以是：___(写出一个即可)，三、解答题31．二次函数y ＝ax 2＋bx ＋c 中的x ，y 满足下表 x … －1 0 1 3 … y…31…不求关系式，仅观察上表，直接写出该函数三条不同类型的性质： （1） ； （2） ； （3） ．32．（1）解方程：27100x x -+= （2）计算：cos60tan 452cos 45︒⨯︒-︒33．如图，二次函数22y ax ax c =-+ (a < 0) 与 x 轴交于 A 、C 两点，与 y 轴交于点 B ，P 为 抛物线的顶点，连接 AB ，已知 OA ：OC=1:3. （1）求 A 、C 两点坐标；（2）过点 B 作 BD ∥x 轴交抛物线于 D ，过点 P 作 PE ∥AB 交 x 轴于 E ，连接 DE ， ①求 E 坐标； ②若 tan ∠BPM=25，求抛物线的解析式．34．如图甲，直线y=﹣x+3与x 轴、y 轴分别交于点B 、点C ，经过B 、C 两点的抛物线y=x 2+bx+c 与x 轴的另一个交点为A ，顶点为P ． （1）求该抛物线的解析式；（2）在该抛物线的对称轴上是否存在点M ，使以C ，P ，M 为顶点的三角形为等腰三角形？若存在，请直接写出所符合条件的点M 的坐标；若不存在，请说明理由； （3）当0＜x ＜3时，在抛物线上求一点E ，使△CBE 的面积有最大值（图乙、丙供画图探究）．35．如图①，抛物线y ＝x 2﹣（a +1）x +a 与x 轴交于A 、B 两点（点A 位于点B 的左侧），与y 轴交于点C ．已知△ABC 的面积为6．（1）求这条抛物线相应的函数表达式；（2）在抛物线上是否存在一点P ，使得∠POB ＝∠CBO ，若存在，请求出点P 的坐标；若不存在，请说明理由；（3）如图②，M 是抛物线上一点，N 是射线CA 上的一点，且M 、N 两点均在第二象限内，A 、N 是位于直线BM 同侧的不同两点．若点M 到x 轴的距离为d ，△MNB 的面积为2d ，且∠MAN ＝∠ANB ，求点N 的坐标．四、压轴题36．如图1，△ABC 中，AB=AC=4，∠BAC=100，D 是BC 的中点．小明对图1进行了如下探究：在线段AD 上任取一点E ，连接EB ．将线段EB 绕点E 逆时针旋转80°，点B 的对应点是点F ，连接BF ，小明发现：随着点E 在线段AD 上位置的变化，点F 的位置也在变化，点F 可能在直线AD 的左侧，也可能在直线AD 上，还可能在直线AD 的右侧．请你帮助小明继续探究，并解答下列问题：（1）如图2，当点F 在直线AD 上时，连接CF ，猜想直线CF 与直线AB 的位置关系，并说明理由．（2）若点F 落在直线AD 的右侧，请在备用图中画出相应的图形，此时（1）中的结论是否仍然成立，为什么？（3）当点E 在线段AD 上运动时，直接写出AF 的最小值．37．问题提出（1）如图①，在ABC 中，2,6,135AB AC BAC ==∠=，求ABC 的面积．问题探究（2）如图②，半圆O 的直径10AB =，C 是半圆AB 的中点，点D 在BC 上，且2CD BD =，点P 是AB 上的动点，试求PC PD +的最小值．问题解决（3）如图③，扇形AOB 的半径为20,45AOB ∠=在AB 选点P ，在边OA 上选点E ，在边OB 上选点F ，求PE EF FP ++的长度的最小值．38．如图，⊙M 与菱形ABCD 在平面直角坐标系中，点M 的坐标为（﹣3，1），点A 的坐标为（2，0），点B 的坐标为（1，﹣3），点D 在x 轴上，且点D 在点A 的右侧． （1）求菱形ABCD 的周长；（2）若⊙M 沿x 轴向右以每秒2个单位长度的速度平移，菱形ABCD 沿x 轴向左以每秒3个单位长度的速度平移，设菱形移动的时间为t （秒），当⊙M 与AD 相切，且切点为AD 的中点时，连接AC ，求t 的值及∠MAC 的度数；（3）在（2）的条件下，当点M 与AC 所在的直线的距离为1时，求t 的值．39．平面直角坐标系xOy 中，矩形OABC 的顶点A ，C 的坐标分别为(2,0)，(0,3)，点D 是经过点B ，C 的抛物线2y x bx c =-++的顶点． （1）求抛物线的解析式；（2）点E 是（1）中抛物线对称轴上一动点，求当△EAB 的周长最小时点E 的坐标； （3）平移抛物线，使抛物线的顶点始终在直线CD 上移动，若平移后的抛物线与射线．．BD 只有一个公共点，直接写出平移后抛物线顶点的横坐标m 的值或取值范围．40．如图，正方形ABCD 中，点O 是线段AD 的中点，连接OC ，点P 是线段OC 上的动点，连接AP 并延长交CD 于点E ，连接DP 并延长交AB 或BC 于点F ， （1）如图①，当点F 与点B 重合时，DEDC等于多少；（2）如图②，当点F 是线段AB 的中点时，求DEDC的值； （3）如图③，若DE CF ，求DEDC的值.【参考答案】***试卷处理标记，请不要删除一、选择题 1．D 解析：D 【解析】 【分析】根据题意画出图形，连接OA 和OB ，根据勾股定理的逆定理得出∠AOB ＝90°，再根据圆周角定理和圆内接四边形的性质求出即可． 【详解】 解：如图所示，连接OA ，OB ， 则OA ＝OB ＝3， ∵AB ＝2， ∴OA 2+OB 2＝AB 2， ∴∠AOB ＝90°，∴劣弧AB 的度数是90°，优弧AB 的度数是360°﹣90°＝270°， ∴弦AB 对的圆周角的度数是45°或135°， 故选：D ． 【点睛】此题主要考查圆周角的求解，解题的关键是根据图形求出圆心角，再得到圆周角的度数.2．D解析：D【解析】【分析】要判断所给方程是有两个不相等的实数根，只要找出方程的判别式，根据判别式的正负情况即可作出判断．有两个不相等的实数根的方程，即判别式的值大于0的一元二次方程．【详解】A、△=0-4×1×1=-4<0，没有实数根；B、△=22-4×1×1=0，有两个相等的实数根；C、△=22-4×1×3=-8<0，没有实数根；D、△=22-4×1×（-3）=16>0，有两个不相等的实数根，故选D．【点睛】本题考查了根的判别式，注意掌握一元二次方程ax2+bx+c=0（a≠0）的根与△=b2-4ac有如下关系：①当△＞0时，方程有两个不相等的两个实数根；②当△=0时，方程有两个相等的两个实数根；③当△＜0时，方程无实数根．3．B解析：B【解析】【分析】通过矩形的性质和等角的条件可得∠BPC=90°，所以P点应该在以BC为直径的圆上，即OP=4，根据两边之差小于第三边及三点共线问题解决.【详解】如图，∵四边形ABCD为矩形，∴AB=CD=3，∠BCD=90°,∴∠PCD+∠PCB=90°,∵PBC PCD∠=∠,∴∠PBC+∠PCB=90°,∴∠BPC=90°,∴点P在以BC为直径的圆⊙O上，在Rt△OCD中，OC=118422BC,CD=3，由勾股定理得，OD=5，∵PD≥OD OP ,∴当P,D,O三点共线时，PD最小，∴PD的最小值为OD-OP=5-4=1.故选：B.【点睛】本题考查矩形的性质，勾股定理，线段最小值问题及圆的性质，分析出P点的运动轨迹是解答此题的关键.4．A解析：A【解析】【分析】根据一元二次方程的定义可得m﹣1≠0，再解即可．【详解】由题意得：m﹣1≠0，解得：m≠1，故选A．【点睛】此题主要考查了一元二次方程的定义，关键是掌握只含有一个未知数，并且未知数的最高次数是2的整式方程叫一元二次方程．5．C解析：C【解析】【分析】根据勾股定理求出AB，根据锐角三角函数的定义求出各个三角函数值，即可得出答案．【详解】如图：由勾股定理得：22222133AC BC++＝＝，所以cosB=313BCAB＝，sinB=21233AC ACtanBAB BC=＝＝，所以只有选项C正确；故选：C．【点睛】此题考查锐角三角函数的定义的应用，能熟记锐角三角函数的定义是解此题的关键．6．D解析：D【解析】【分析】抛物线y=(x+1)2-2开口向上，有最小值，顶点坐标为(-1，-2)，顶点的纵坐标-2即为函数的最小值.【详解】解：根据二次函数的性质，当x=-1时，二次函数y=(x+1)2-2的最小值是-2.故选D.【点睛】本题考查了二次函数的最值.7．A解析：A【解析】将二次函数22y x =的图象向右平移3个单位，再向上平移2个单位后的函数关系式为：22(3)2y x =-+.故选A.8．C解析：C【解析】【分析】设方程2(1)(1)0a x b x c -+-+=中，1t x =-，根据已知方程的解，即可求出关于t 的方程的解，然后根据1t x =-即可求出结论．【详解】解：设方程2(1)(1)0a x b x c -+-+=中，1t x =-则方程变为20at bt c ++=∵关于x 的方程20ax bx c ++=的解为11x =-，23x =，∴关于t 的方程20at bt c ++=的解为11t =-，23t =， ∴对于方程2(1)(1)0a x b x c -+-+=，11x -=-或3解得：10x =，24x =，故选C ．【点睛】此题考查的是根据已知方程的解，求新方程的解，掌握换元法是解决此题的关键．9．B解析：B【解析】【分析】根据圆心距和两圆半径的之间关系可得出两圆之间的位置关系．【详解】∵⊙O 的直径为4，∴⊙O 的半径为2，∵圆心O 到直线l 的距离是2，∴根据圆心距与半径之间的数量关系可知直线l 与⊙O 的位置关系是相切．故选：B ．【点睛】本题考查了直线和圆的位置关系的应用，理解直线和圆的位置关系的内容是解此题的关键，注意：已知圆的半径是r ，圆心到直线的距离是d ，当d ＝r 时，直线和圆相切，当d ＞r 时，直线和圆相离，当d ＜r 时，直线和圆相交．10．A解析：A【解析】【分析】根据极差的概念最大值减去最小值即可求解．【详解】解：这组数据：0、－1、3、2、1的极差是：3-（-1）=4．故选A ．【点睛】本题考查了极差的知识，极差是指一组数据中最大数据与最小数据的差．11．A解析：A【解析】【分析】直接把已知数据代入进而得出c 的值，再解方程根据根的判别式分析即可．【详解】∵x ＝﹣1为方程x 2﹣8x ﹣c ＝0的根，1+8﹣c ＝0，解得c ＝9，∴原方程为x 2－8x ＋9＝0，∵24b ac ∆=-＝（﹣8）2－4×9＞0，∴方程有两个不相等的实数根．故选：A ．【点睛】本题考查一元二次方程的解、一元二次方程根的判别式，解题的关键是掌握一元二次方程根的判别式，对于一元二次方程()200++=≠ax bx c a ，根的情况由24b ac ∆=-来判别，当24b ac -＞0时，方程有两个不相等的实数根，当24b ac -＝0时，方程有两个相等的实数根，当24b ac -＜0时，方程没有实数根．12．D解析：D【解析】【分析】根据题目中的函数解析式和二次函数的性质，可以判断各个选项中的结论是否正确，从而可以解答本题．【详解】解：∵二次函数y ＝﹣x 2+x ＝﹣(x 12-)2+14， ∴a ＝﹣1，该函数的图象开口向下，故选项A 错误；对称轴是直线x ＝12，故选项B 错误； 当x ＝12时取得最大值14，该函数有最高点，故选项C 错误； 在对称轴右侧的部分从左往右是下降的，故选项D 正确；故选：D ．【点睛】本题考查了二次函数的性质，掌握函数解析式和二次函数的性质是解题的关键．13．D解析：D【解析】【分析】作PB ⊥OA 于B ，如图，根据垂径定理得到OB =AB ，则S △POB =S △PAB ，再根据反比例函数k 的几何意义得到S △POB =12|k |，所以S =2k ，为定值． 【详解】作PB ⊥OA 于B ，如图，则OB =AB ，∴S △POB =S △PAB ． ∵S △POB =12|k |，∴S =2k ，∴S 的值为定值． 故选D ．本题考查了反比例函数系数k的几何意义：在反比例函数y=kx图象中任取一点，过这一个点向x轴和y轴分别作垂线，与坐标轴围成的矩形的面积是定值|k|．14．B解析：B【解析】试题分析：△ABC中，∠ABC=90°，AB=6，BC=3，AB：BC=2．A、当点E的坐标为（6，0）时，∠CDE=90°，CD=2，DE=1，则AB：BC=CD：DE，△CDE∽△ABC，故本选项不符合题意；B、当点E的坐标为（6，3）时，∠CDE=90°，CD=2，DE=2，则AB：BC≠CD：DE，△CDE与△ABC不相似，故本选项符合题意；C、当点E的坐标为（6，5）时，∠CDE=90°，CD=2，DE=4，则AB：BC=DE：CD，△EDC∽△ABC，故本选项不符合题意；D、当点E的坐标为（4，2）时，∠ECD=90°，CD=2，CE=1，则AB：BC=CD：CE，△DCE∽△ABC，故本选项不符合题意．故选B．15．B解析：B【解析】【分析】【详解】解：∵抛物线和x轴有两个交点，∴b2﹣4ac＞0，∴4ac﹣b2＜0，∴①正确；∵对称轴是直线x﹣1，和x轴的一个交点在点（0，0）和点（1，0）之间，∴抛物线和x轴的另一个交点在（﹣3，0）和（﹣2，0）之间，∴把（﹣2，0）代入抛物线得：y=4a﹣2b+c＞0，∴4a+c＞2b，∴②错误；∵把（1，0）代入抛物线得：y=a+b+c＜0，∴2a+2b+2c＜0，∵b=2a，∴3b，2c＜0，∴③正确；∵抛物线的对称轴是直线x=﹣1，∴y=a﹣b+c的值最大，即把（m，0）（m≠0）代入得：y=am2+bm+c＜a﹣b+c，∴am2+bm+b＜a，即m（am+b）+b＜a，∴④正确；即正确的有3个，考点：二次函数图象与系数的关系二、填空题16．1：9．【解析】试题分析：由DE∥BC，可得△ADE∽△ABC，根据相似三角形的面积之比等于相似比的平方可得S△ADE：S△ABC=（AD：AB）2=1：9.考点：相似三角形的性质.解析：1：9．【解析】试题分析：由DE∥BC，可得△ADE∽△ABC，根据相似三角形的面积之比等于相似比的平方可得S△ADE：S△ABC=（AD：AB）2=1：9.考点：相似三角形的性质.17．【解析】试题分析：连接BC，∴∠D=∠A，∵AB是⊙O的直径，∴∠ACB=90°，∵AB=3×2=6，AC=2，∴cosD=cosA===．故答案为．考点：1．圆周角定理；2．解直角三角形解析：1 3【解析】试题分析：连接BC，∴∠D=∠A，∵AB是⊙O的直径，∴∠ACB=90°，∵AB=3×2=6，AC=2，∴cosD=cosA=ACAB=26=13．故答案为13．考点：1．圆周角定理；2．解直角三角形．18．红【解析】【分析】哪一种颜色多，指针指向那种颜色的可能性就大．【详解】∵转盘分成6个大小相同的扇形，红色的有3块，∴转动一次转盘后，指针指向红颜色的可能性大．故答案为：红．【点睛】解析：红【解析】【分析】哪一种颜色多，指针指向那种颜色的可能性就大．【详解】∵转盘分成6个大小相同的扇形，红色的有3块，∴转动一次转盘后，指针指向红颜色的可能性大．故答案为：红．【点睛】本题考查了可能性大小的知识，解题的关键是看清那种颜色的最多，难度不大．19．【解析】【分析】根据旋转性质及直角三角形斜边中线等于斜边一半，求出CD=CE=5,再根据勾股定理求DE长，的值即为等腰△CDE底角的正弦值，根据等腰三角形三线合一构建直角三角形求解.【详解】【解析】【分析】根据旋转性质及直角三角形斜边中线等于斜边一半，求出CD=CE=5,再根据勾股定理求DE 长，sin DEC∠的值即为等腰△CDE底角的正弦值，根据等腰三角形三线合一构建直角三角形求解.【详解】如图，过D点作DM⊥BC，垂足为M，过C作CN⊥DE，垂足为N，在Rt△ACB中，AC=8，BC=6，由勾股定理得，AB=10，∵D为AB的中点，∴CD=15 2AB= ,由旋转可得，∠MCN=90°,MN=10，∵E为MN的中点，∴CE=15 2MN,∵DM⊥BC,DC=DB,∴CM=BM=13 2BC ,∴EM=CE-CM=5-3=2，∵DM=14 2AC,∴由勾股定理得，DE=25，∵CD=CE=5，CN⊥DE,∴DN=EN=5 ,∴由勾股定理得，CN=25,∴sin∠DEC=25 CNCE.25.【点睛】本题考查旋转性质，直角三角形的性质和等腰三角形的性质，能够用等腰三角形三线合一的性质构建直角三角形解决问题是解答此题的关键.20．【解析】【分析】根据条件可知a与b的数量关系，然后代入原式即可求出答案．【详解】∵＝，∴b=a,∴=,故答案为：.【点睛】本题考查了分式，解题的关键是熟练运用分式的运算法则．解析：5 3【解析】【分析】根据条件可知a与b的数量关系，然后代入原式即可求出答案．【详解】∵a b b -＝23， ∴b=35a, ∴a b =5335a a =, 故答案为：53. 【点睛】本题考查了分式，解题的关键是熟练运用分式的运算法则． 21．（2，1）【解析】【分析】将二次函数解析式化为顶点式，即可得到顶点坐标.【详解】将二次函数配方得则顶点坐标为（2，1）考点：二次函数的图象和性质．解析：（2，1）【解析】【分析】将二次函数解析式化为顶点式，即可得到顶点坐标.【详解】将二次函数245y x x =-+配方得22()1y x =-+则顶点坐标为（2，1）考点：二次函数的图象和性质． 22．【解析】【分析】直接利用黄金分割的定义求解．【详解】解：∵点C 是线段AB 的黄金分割点且AC ＞BC ，∴AC＝AB ．故答案为:．【点睛】本题考查了黄金分割的定义，点C 是线段AB 的黄金分解析：512- 【解析】 【分析】 直接利用黄金分割的定义求解．【详解】解：∵点C 是线段AB 的黄金分割点且AC ＞BC ，∴AC ＝51-AB ． 故答案为:512-． 【点睛】 本题考查了黄金分割的定义，点C 是线段AB 的黄金分割点且AC ＞BC ，则51AC BC -=，正确理解黄金分割的定义是解题的关键.23．【解析】【分析】过点作的垂线，则得到两个直角三角形，根据勾股定理和正余弦公式，求的长.【详解】过作于点，设，则，因为，所以，则由勾股定理得，因为，所以，则．则．【点睛】本题考查勾股定解析：2【解析】【分析】过A 点作BC 的垂线，则得到两个直角三角形，根据勾股定理和正余弦公式，求AC 的长.【详解】过A 作AD BC ⊥于D 点，设2AC x =，则2AB x =，因为45C ∠=︒，所以AD CD x ==，则由勾股定理得223BD AB AD x =-=，因为62BC =+，所以362BC x x =+=+，则2x =．则2AC =．【点睛】本题考查勾股定理和正余弦公式的运用，要学会通过作辅助线得到特殊三角形，以便求解.24．>【解析】【分析】根据题意直接利用二次函数的图象与a 的关系即可得出答案．【详解】解：因为二次函数的图像开口方向向上，所以有>0.故填>.【点睛】本题主要考查二次函数的性质，掌握二次解析：>【解析】【分析】根据题意直接利用二次函数的图象与a 的关系即可得出答案．【详解】解：因为二次函数2y ax bx c =++的图像开口方向向上，所以有a >0.故填>.【点睛】本题主要考查二次函数的性质，掌握二次项系数a 与抛物线的关系是解题的关键，图像开口方向向上，a >0；图像开口方向向下，a <0． 25．25%【解析】【分析】设每次降价的百分比为x ，根据前量80，后量45，列出方程，解方程即可得到答案.【详解】设每次降价的百分比为x ，，解得：x1=0.25=25%，x2=1.75（不合解析：25%【解析】【分析】设每次降价的百分比为x ，根据前量80，后量45，列出方程280(1)45x ，解方程即可得到答案.【详解】设每次降价的百分比为x，2x，80(1)45解得：x1=0.25=25%，x2=1.75（不合题意舍去）故答案为：25%.【点睛】此题考查一元二次方程的实际应用，正确理解百分率问题，代入公式：前量（1 x）2=后量，即可解答此类问题.26．4【解析】【分析】先列举出所有上升数，再根据概率公式解答即可．【详解】解：两位数一共有99-10+1=90个，上升数为：共8+7+6+5+4+3+2+1=36个．概率为36÷90=解析：4【解析】【分析】先列举出所有上升数，再根据概率公式解答即可．【详解】解：两位数一共有99-10+1=90个，上升数为：共8+7+6+5+4+3+2+1=36个．概率为36÷90=0.4．故答案为：0.4．27．【解析】【分析】如图，过点D 作DF⊥BC 于F ，由“SAS”可证△ACQ≌△BCP，可得AQ ＝BP ，∠CAQ＝∠CBP，由直角三角形的性质和勾股定理可求BD 的长，由锐角三角函数可求BP 的长，由相解析：677【解析】【分析】如图，过点D 作DF ⊥BC 于F ，由“SAS ”可证△ACQ ≌△BCP ，可得AQ ＝BP ，∠CAQ ＝∠CBP ，由直角三角形的性质和勾股定理可求BD 的长，由锐角三角函数可求BP 的长，由相似三角形的性质可求AE 的长，即可求解．【详解】如图，过点D 作DF ⊥BC 于F ，∵△ABC ，△PQC 是等边三角形，∴BC ＝AC ，PC ＝CQ ，∠BCA ＝∠PCQ ＝60°，∴∠BCP ＝∠ACQ ，且AC ＝BC ，CQ ＝PC ， ∴△ACQ ≌△BCP （SAS ）∴AQ ＝BP ，∠CAQ ＝∠CBP ，∵AC ＝6，AD ＝2， ∴CD ＝4，∵∠ACB ＝60°，DF ⊥BC ，∴∠CDF ＝30°，∴CF ＝12CD ＝2，DF ＝CF ÷tan30°3＝3 ∴BF ＝4，∴BD 22DF BF +1612+7，∵△CPQ 是等边三角形，∴S △CPQ ＝34CP 2， ∴当CP ⊥BD 时，△CPQ 面积最小，∴cos ∠CBD ＝BP BF BC BD =， ∴627BP =，∴BP ＝7，∴AQ ＝BP ， ∵∠CAQ ＝∠CBP ，∠ADE ＝∠BDC ，∴△ADE ∽△BDC ， ∴AE AD BC BD=， ∴6AE =，∴AE ＝7，∴QE ＝AQ−AE ．． 【点睛】 本题考查了全等三角形的判定和性质，等边三角形的性质，锐角三角函数，相似三角形的判定和性质，直角三角形的性质，勾股定理等知识，求出BP 的长是本题的关键． 28．2【解析】【分析】根据根与系数的关系确定和，然后代入计算即可．【详解】解：∵∴=-3, =-5∴-3-(-5)=2故答案为2．【点睛】本题主要考查了根与系数的关系，牢记对于(a≠解析：2【解析】【分析】根据根与系数的关系确定12x x +和12x x •，然后代入计算即可．【详解】解：∵2350x x +-=∴12x x +=-3, 12x x •=-5∴1212x x x x +-•=-3-(-5)=2故答案为2．【点睛】本题主要考查了根与系数的关系，牢记对于20ax bx c ++=(a≠0),则有：12b x x a +=-，12c x x a•=是解答本题的关键． 29．8【解析】【分析】首先求出A 、B 的坐标，然后根据坐标求出AB 、CD 的长，再根据三角形面积公式计算即可．【详解】解：∵y＝x2﹣2x ﹣3，设y ＝0，∴0＝x2﹣2x ﹣3，解得：x1＝3，解析：8【解析】【分析】首先求出A 、B 的坐标，然后根据坐标求出AB 、CD 的长，再根据三角形面积公式计算即可．【详解】解：∵y ＝x 2﹣2x ﹣3，设y ＝0，∴0＝x 2﹣2x ﹣3，解得：x 1＝3，x 2＝﹣1，即A 点的坐标是（﹣1，0），B 点的坐标是（3，0），∵y ＝x 2﹣2x ﹣3，＝（x ﹣1）2﹣4，∴顶点C 的坐标是（1，﹣4），∴△ABC 的面积＝12×4×4＝8， 故答案为8．【点睛】本题考查了抛物线与x 轴的交点，二次函数的性质，二次函数的三种形式的应用，主要考查学生运用性质进行计算的能力，题目比较典型，难度适中． 30．∠ACP=∠B（或）．【分析】由于△ACP与△ABC有一个公共角，所以可利用两组对应边的比相等且夹角对应相等的两个三角形相似或有两组角对应相等的两个三角形相似进行添加条件．【详解】解析：∠ACP=∠B（或AP ACAC AB=）．【解析】【分析】由于△ACP与△ABC有一个公共角，所以可利用两组对应边的比相等且夹角对应相等的两个三角形相似或有两组角对应相等的两个三角形相似进行添加条件．【详解】解：∵∠PAC=∠CAB，∴当∠ACP=∠B时，△ACP∽△ABC；当AP ACAC AB=时，△ACP∽△ABC．故答案为：∠ACP=∠B（或AP ACAC AB=）．【点睛】本题考查了相似三角形的判定：两组对应边的比相等且夹角对应相等的两个三角形相似：有两组角对应相等的两个三角形相似．三、解答题31．（1）抛物线与x轴交于点（-1,0）和（3,0）；与y轴交于点（0,3）；（2）抛物线的对称轴为直线x=1;（3）当x＜1时，y随x的增大而增大【解析】【分析】根据表格中数据，可得抛物线与x轴交点坐标，与y轴交点坐标，抛物线的对称轴直线以及抛物线在对称轴左侧的增减性，从而进行解答.【详解】解：由表格数据可知：当x=0时，y=3；当y=0时，x=-1或3∴该函数三条不同的性质为：（1）抛物线与x轴交于点（-1,0）和（3,0）；与y轴交于点（0,3）；（2）抛物线的对称轴为直线x=1;（3）当x＜1时，y随x的增大而增大【点睛】本题考查二次函数性质，数形结合思想解题是本题的解题关键.32．（1）∴x1＝2，x2＝5；（2）1 2 -【分析】（1）用因式分解法解一元二次方程；（2）先将特殊角三角形函数值代入，然后进行实数的混合运算．【详解】解：（1）27100x x -+=(2)(5)0x x --=∴x 1＝2，x 2＝5（2）cos60tan 4545︒⨯︒-︒112=⨯ 12=-． 【点睛】本题考查解一元二次方程，特殊角三角函数值的混合运算，掌握运算法则正确计算是解题关键．33．（1）A （-1，0），C （3，0）；（2）① E （-13，0）；②原函数解析式为：2515522y x x =-++． 【解析】【分析】(1)由二次函数的解析式可求出对称轴为x=1，过点P 作PE ⊥x 轴于点E,所以设A （-m ，0），C （3m ，0），结合对称轴即可求出结果；(2) ①过点P 作PM ⊥x 轴于点M ，连接PE ，DE ，先证明△ABO △EPM 得到AO EM OB PM =，找出OE=a c-，再根据A （-1，0）代入解析式得：3a+c=0，c=-3a ，即可求出OE 的长，则坐标即可找到；②设PM 交BD 于点N ；根据点P （1，c-a ），BN ‖AC ，PM ⊥x 轴表示出PN=-a ，再由tan ∠BPM=25PN BN =求出a ，结合（1）知道c ，即可知道函数解析式． 【详解】（1）∵二次函数为：22y ax ax c =-+(a<0)， ∴对称轴为2122b a x a a-=-=-=， 过点P 作PM ⊥x 轴于点M ，则M （1，0），M 为AC 中点，又OA ：OC=1：3，设A （-m ，0），C （3m ，0），∴231m m -+=， 解得：m=1， ∴A （-1，0），C （3，0），（2）①做图如下：∵PE ∥AB ，∴∠BAO=∠PEM ，又∠AOB=∠EMP ，∴△ABO△EPM ， ∴AO EM OB PM= ， 由（1）知：A （-1，0），C （3，0），M （1，0），B （0，c ），P （1，c-a ）， ∴11OE c c a +=-， ∴OE=a c-， 将A （-1，0）代入解析式得：3a+c=0，∴c=-3a ，∴133a a OE c a =-== ， ∴E （-13，0）； ②设PM 交BD 于点N ；∵22y ax ax c =-+(a<0)，∴x=1时，y=c-a ，即点P （1，c-a ），∵BN ‖AC ，PM ⊥x 轴∴NM= BO=c ，BN=OM=1，∴PN=-a ，∵tan ∠BPM=25， ∴tan ∠BPM=25BN PN =， ∴PN=52， 即a=-52， 由（1）知c=-3a ，∴c=152； ∴原函数解析式为：2515522y x x =-++． 【点睛】 此题考查了抛物线与x 轴的交点；二次函数的性质，待定系数法求二次函数解析式． 34．（1）y=x 2﹣4x+3；（2）（2，）或（2，7）或（2，﹣1+2）或（2，﹣1﹣2）；（3）E 点坐标为（，）时，△CBE 的面积最大． 【解析】试题分析：（1）由直线解析式可求得B 、C 坐标，利用待定系数法可求得抛物线解析式； （2）由抛物线解析式可求得P 点坐标及对称轴，可设出M 点坐标，表示出MC 、MP 和PC 的长，分MC=MP 、MC=PC 和MP=PC 三种情况，可分别得到关于M 点坐标的方程，可求得M 点的坐标；（3）过E 作EF ⊥x 轴，交直线BC 于点F ，交x 轴于点D ，可设出E 点坐标，表示出F 点的坐标，表示出EF的长，进一步可表示出△CBE的面积，利用二次函数的性质可求得其取得最大值时E点的坐标．试题解析：（1）∵直线y=﹣x+3与x轴、y轴分别交于点B、点C，∴B（3，0），C（0，3），把B、C坐标代入抛物线解析式可得，解得，∴抛物线解析式为y=x2﹣4x+3；（2）∵y=x2﹣4x+3=（x﹣2）2﹣1，∴抛物线对称轴为x=2，P（2，﹣1），设M（2，t），且C（0，3），∴MC=，MP=|t+1|，PC=，∵△CPM为等腰三角形，∴有MC=MP、MC=PC和MP=PC三种情况，①当MC=MP时，则有=|t+1|，解得t=，此时M（2，）；②当MC=PC时，则有=2，解得t=﹣1（与P点重合，舍去）或t=7，此时M（2，7）；③当MP=PC时，则有|t+1|=2，解得t=﹣1+2或t=﹣1﹣2，此时M（2，﹣1+2）或（2，﹣1﹣2）；综上可知存在满足条件的点M，其坐标为（2，）或（2，7）或（2，﹣1+2）或（2，﹣1﹣2）；（3）如图，过E作EF⊥x轴，交BC于点F，交x轴于点D，设E（x，x2﹣4x+3），则F（x，﹣x+3），∵0＜x＜3，∴EF=﹣x+3﹣（x2﹣4x+3）=﹣x2+3x，∴S△CBE=S△EFC+S△EFB=EF•OD+EF•BD=EF•OB=×3（﹣x2+3x）=﹣（x﹣）2+，∴当x=时，△CBE的面积最大，此时E点坐标为（，），。
2020年徐汇区西南模范中学初三3月月考卷
2020年徐汇区西南模范中学初三3月月考卷the best answer31、What did the teacher ___________ you to __________ at the meeting?A、tell…sayB、ask…speakC、tell…speakD、ask…talk32、 I remember ___________ a telephone call to Miss Li last night、A、 makeB、 to makeC、 makingD、 made33、 Our teacher, together with all the students,__________ morning exercise every day、A、 doB、 doesC、 is doingD、 are doing34、 The workers in the city ____________ for more than sixteen hours a day in old days、A、 are made to workB、 are made workC、 were made to workD、 were made work35、 This winter was not too cold、 The ice in the river was too thin for us _____________、A、 to skate on itB、 skating on itC、 to skate onD、 skating on36、 The number of students who ___________ the English club _____________20、A、 take part in, isB、 join, areC、 take part in, areD、 join, is37、 Mike studies ___________ Mary、A、 not so hardly asB、 as hardly asC、 as hard asD、 not as hard as38、 They go to see their grandparents ____________ Sunday morning、A、 in everyB、 everyC、 on everyD、 in39、We had no ___________ in finding the doctor’s address、A、 problemB、 troubleC、 questionD、 matter40、 Yesterday I met Miss Li in the street、 She told me that she ____________ to Japan twice、A、 has beenB、 wentC、 had beenD、 has gone41、Last Teachers’ Day, the teachers received a box ____________ card、A、 was filled withB、 full ofC、 fill withD、 fulled with42、 He will take part in the beginning ceremony when the new hospital ___________ to the public、A、 is openB、 is openedC、 will openD、 will be opened43、– Do you mind my taking this seat?______________、A、 Yes, sit down, please、B、 Yes, take it, please、C、 No, of course not、D、No, you can’t take it、44、 He left the meeting early because he had to__________ his son from school、A、 pick upB、 put upC、 take upD、 bring up45、 Mr、Black didn’t go to work yesterday because he was ill in __________ bed、A、 aB、 anC、 theD、 /46、 She has made many friends ___________ she came to our school、A、 beforeB、 afterC、 sinceD、 until47、 I am ___________ your view on spending pocket money、It’s reasonable、A、 in favour ofB、 in charge ofC、 afraid ofD、 famous for48、 The girl needs some help, _____________?A、 does sheB、 need sheC、doesn’t sheD、needn’t she49、 The characters need strong personalities____________ will come across in the picture、A、 whoB、 whichC、 whenD、 where50、 Steam ___________ from the basin after heating the water、A、 was seen riseB、 was seen to raiseC、 was seen raisingD、 was seen rising II、 Complete the following passage with words or phrases in the box、 Each word can only be used once、A、 during the last few hoursB、 a great helpC、 in spaceD、 older onesE、 earlier onesF、 how the weather will changeG、 take picturesH、 be able toI、 forms Now satellites are helping to forecast (预报)the weather、 They are ______51_______, and they can reach any part of the world、 The satellites______52______ of the atmosphere (大气), because this is where the weather ______53_______、 They send these pictures to the weather stations、 So meteorologists (气象学家)can see the weather of any part of the world、 From the pictures, the scientists can often say_______54______、 Today, nearly five hundred weather stations in sixty countries receive satellite pictures、When they receive new pictures, the meteorologists compare them with ______55______、 Perhaps they may find that the clouds have changed ______56______、 This may mean that the weather on the ground may soon change, too、 In their next weather forecast, the meteorologists can say this、 So the weather satellites are_____57______ to the meteorologists、 Before satellites were invented, the scientists could forecast the weather for about24 or48 hours、 Now they can make good forecasts for three or five days、 Soon, perhaps, they may______58______ forecast the weather for a week or moreahead (提前)、III、 Complete the sentences with the given words in their proper forms、59、It’s amazing to see the _____________ areas in France、 (scene)60、Do you know the _____________ “Practice makes perfect”? (say)61、He’s old-fashioned and never ___________ his style、 (vary)62、 Tom and Tim are twins, but they have different _______________、 (person)63、 He was one of the ____________ artists of his time、 (lead)64、 We can use sound effects of add ____________、(exciting)65、 For _____________, some comic strips have no frame borders、 (vary)66、 The young man was lucky enough to be still____________ after the accident、 (living)IV、 Rewrite the sentences as required67、If she doesn’t come on time, we’ll go without her、 (保持原意)We’ll go without her _____________ she _____________ on time、68、 The boy was too frightened to say a word、 (保持原意)The boy was __________ frightened that he __________ say a word、69、 The coat cost Mary nearly a month salary,___________ ___________? (反义疑问句)70、He was so fat that he couldn’t get through the door、 (保持原意)He was not _________ ___________ to get through the door、71、Did the policemen catch the robber? (改被动语态)____________ the robber ____________ by the policemen?72、 Noise pollution makes people talk more loudlythan before、 (保持原意)People have __________ talk more loudly than before___________ of noise pollution、73、“Has Bob been to London?” Tom asked、 (改为宾语从句)Tom asked ___________ Bob ___________ been toLondon、C、 Read the passage and fill in the blanks with proper words、 Do you love holidays, but hate the increase in weight that follows? You are not alone、Holidays are happy days with p_____86______ and delicious foods、 But many people are worried about the weight that comes with these delicious foods、 With proper planning, it is possible to c______87_____ your weight、 The ideais to enjoy the holidays but not to eat too much、 You don’t have to turn away from the foods that you enjoy、The following advice may be of some help to you、 Do not m______88_____ meals、 Before you leave home for a party, have a small, low-fat meal or fast food、 This may help to keep you from getting too excited before the wonderful foods、 Begin with clear soup and fruit or vegetables、 A large glass of water before you eat may help you feel full、 Use a small plate; a large plate may make you eat m______89______ than enough、 Better not have high-fat foods、 Choose lean(瘦的)meats、 Fill your plate with salad and green vegetables、 Try mints (薄荷)and fruits i______90____ you have a sweet tooth、They do not have fat l_____91_____ cream and chocolate、Don’t let exercise take a b______92______ during th e holidays、 A20-minute walk after a meal can help you burn off excess calories、 (多余的热量)D、 Answer the questions (根据短文内容回答下列问题）No matter what happens, I ll always be there for youIn1989 an8、2 earthquake almost flattened America, killing over30,000 people in less than four minutes、 In the midst of utter devastation and chaos, a father left his wife safely at home and rushed to the school where his son was supposed to be, only to discover that thebuilding was as flat as a pancake、 After the unforgettably initial shock, he remembered the promise he had made to his son: "No matter what, Ill always be there for you!" And tears began to fill his eyes、 As he looked at the pile of ruins that once was the school, it looked hopeless, but he kept remembering his commitment to his son、He began to direct his attention towards where he walked his son to class at school each morning、Remembering his sons classroom would be in the back right corner of the building, he rushed there and started digging through the ruins、As he was digging, otherhelpless parents arrived, clutching their hearts, saying: "My son!" "My daughter!" Other well-meaning parents tried to pull him off what was left of the school, saying: "Its too late! Theyre all dead! You cant help! Go home! Come on, face reality, theres nothing you can do!" To each parent he responded with one line: "Are you going to help me now?" And then he continued to dig for his son, stone by stone、 The fire chief showed up and tried to pull him off the schools ruins saying, "Fires are breaking out, explosions are happening everywhere、 Youre in danger、Well take care of it、 Go home、" To which this loving, caring American father asked, "Are you going to help me now?" The police came and said, "Youre angry, anxious and its over、 Youre endangering others、 Go home、 Well handle it!" To which he replied, "Are you going to help me now?" No one helped、Courageously he went on alone because he needed to know for himself: "Is my boy alive or is he dead?" He dug for eight hours、、、12 hours、、、24 hours、、、36 hours、、、then, in the38th hour, he pulled back a large stone and heard his sons voice、 He screamed his sons name, "ARMAND!" He heard back, "Dad!?! Its me, Dad! I told the other kids not toworry、 I told them that if you were alive, youd save me and when you saved me, theyd be saved、 You promised, No matter what happens, youll always be there for you! You did it, Dad!" "Whats going on in there? How is it?" the father asked、"There are14 of us left out of33, Dad、Were scared, hungry, thirsty and thankful youre here、When the building collapsed, it made a triangle, and it saved us、""Come out, boy!""No, Dad! Let the other kids out first, cause I know youll get me! No matter what happens, I know youll always be there for me!"93、 No one knew what would happen,didthey ?_______________________________________________94、 How many people lost their lives in the Earthquake in less than fourminutes?________________________________________________95、 Why was the father so insistent that he kept looking for hisson ?_______________________________________________96、 All of the parents were looking for their children,weren’tthey ?_________________________________________________97、 What do you think of thestory ?__________________________________________________98、 How do you feel about thestory ?_________________________________________________首字母附加篇The world p_______is growing very fast、 In thelast40 years ,it has doubled 、 By the year2200, it will be about10 billion、 Our cities will be much bigger、There will be more factories and more roads、 We will need more water and other natural r_______、 Therefore, we will have serious problems in the future, so we must change the way we use e_______and natural resources now、Every day we throw away millions of tons of rubbish、Half of this is paper that we can use again、 Ana_______family in Europe or America throws away more than one ton of rubbish each year, but we can r______much of it、 If we recycle things, we can save money,energy and resources、 A lot of rubbish, however,cannot be recycled、 P________and chemicals will not disappear for hundreds of years、 They pollute the air, the land and the water、 Pollution will be an even bigger problem in the future、 Therefore, we must stop using m_______likeplastics and chemicals、 Many natural resources cannot be r_______、 Coal and minerals, for example, will be used up some day、 Other resources take a long time to grow, such as trees, or they may not always be a______, such as water、 We must learn to use less energy and fewer resources、 We also have to find other w_______to make energy 、 We can find ways to use the sun, the wind and the sea、KeysI、 A C B C C D C B B C B B C A D C A C B D II、 C G I F E A B H III、 scenic saying varies personalities leading excitement variety alive IV、unless comes so couldn’t didn’t it thin enough was caught to because if had C篇pleasant control miss more if like break D篇93、No,they didn’t94、 Over30000 people95、 Because he made the promise to his son that no matter what ,he would always be there for him、96、No ,they weren’t97、it’s moving98、 He is a brave boy附加篇：Population resources energy average reduce Plastics materials renewable available ways。
2017年上海徐汇区初三一模数学试卷答案
=
3+2
=
5 ，不正确．
h y
2
2
i.iz ．∵ ， D
2x = 3y
osh ∴ x
2
=
jia y
3
∴ x = 3 = 3 ，不正确．
x+y
3+2
5
故选B．
2. 如果一斜坡的坡比是1 : 2.4，那么该斜坡坡角的余弦值是（ ）．
A. 12
5
B. 5
12
C. 5
13
答案 D
解析
如图所示：
由题意，得：tan α = i =
．
答 案 √3 : 2
解 析 ∵两个相似三角形的对应中线比是√3 : 2， ∴它们的周长比为√3 : 2．
2018/12/04 11. 如果点P 是线段AB的黄金分割点（AP > BP ），那么请你写出一个关于线段AP 、BP 、AB之间的数量关系的等式，你的
结论是：
．
答案 解析
AP 2 = BP ⋅ AB
2
2
∴ ， 1
1
⋅ AP ⋅ BE = ⋅ DF ⋅ AQ
2
2
−−
∴ ． AP
2√3
2√39
AQ
=
−− √13
=
13
−−
故答案为 2√39 ．
13
解答题：（本大题共7题，第19-22题每题10分，第23、24题每题12分，第25题14分，满分78分）
19. 计算： ∘
∘
∘
2sin 60 − |cot30 − cot45 | +
3
B.
x =3
x−y
答案 B
2017年徐汇区西南模范中学初三3月月考卷
2017年3月西南模范初三测试卷I. Choose the best answer31. What did the teacher ___________ you to __________ at the meeting?A. tell…sayB. ask…speakC. tell…speakD. ask…talk32. I remember ___________ a telephone call to Miss Li last night.A. makeB. to makeC. makingD. made33. Our teacher, together with all the students, __________ morning exercise every day.A. doB. doesC. is doingD. are doing34. The workers in the city ____________ for more than sixteen hours a day in old days.A. are made to workB. are made workC. were made to workD. were made work35. This winter was not too cold. The ice in the river was too thin for us _____________.A. to skate on itB. skating on itC. to skate onD. skating on36. The number of students who ___________ the English club _____________20.A. take part in, isB. join, areC. take part in, areD. join, is37. Mike studies ___________ Mary.A. not so hardly asB. as hardly asC. as hard asD. not as hard as38. They go to see their grandparents ____________ Sunday morning.A. in everyB. everyC. on everyD. in39. We had no ___________ in finding the doctor’s address.A. problemB. troubleC. questionD. matter40. Yesterday I met Miss Li in the street. She told me that she ____________ to Japan twice.A. has beenB. wentC. had beenD. has gone41. Last Teachers’ Day, the teachers received a box ____________ card.A. was filled withB. full ofC. fill withD. fulled with42. He will take part in the beginning ceremony when the new hospital ___________ to the public.A. is openB. is openedC. will openD. will be opened43. – Do you mind my taking this seat?-- ______________.A. Yes, sit down, please.B. Yes, take it, please.C. No, of course not.D. No, you can’t take it.44. He left the meeting early because he had to __________ his son from school.A. pick upB. put upC. take upD. bring up45. Mr. Black didn’t go to work yesterday because he was ill in __________ bed.A. aB. anC. theD. /46. She has made many friends ___________ she came to our school.A. beforeB. afterC. sinceD. until47. I am ___________ your view on spending pocket money. It’s reasonable.A. in favour ofB. in charge ofC. afraid ofD. famous for48. The girl needs some help, _____________?A. does sheB. need sheC. doesn’t sheD. needn’t she49. The characters need strong personalities ____________ will come across in the picture.A. whoB. whichC. whenD. where50. Steam ___________ from the basin after heating the water.A. was seen riseB. was seen to raiseC. was seen raisingD. was seen risingII. Complete the following passage with words or phrases in the box. Each word can only be usedNow satellites are helping to forecast (预报) the weather. They are ______51_______, and they can reach any part of the world. The satellites ______52______ of the atmosphere (大气), because this is where the weather ______53_______. They send these pictures to the weather stations. So meteorologists (气象学家) can see the weather of any part of the world. From the pictures, the scientists can often say _______54______.Today, nearly five hundred weather stations in sixty countries receive satellite pictures. When they receive new pictures, the meteorologists compare them with ______55______. Perhaps they may find that the clouds have changed ______56______. This may mean that the weather on the ground may soon change, too. In their next weather forecast, the meteorologists can say this.So the weather satellites are _____57______ to the meteorologists. Before satellites were invented, the scientists could forecast the weather for about 24 or 48 hours. Now they can make good forecasts for three or five days. Soon, perhaps, they may ______58______ forecast the weather for a week or more ahead (提前).III. Complete the sentences with the given words in their proper forms.59. It’s amazing to see the _____________ areas in France. (scene)60. Do you know the _____________ “Practice makes perfect”? (say)61. He’s old-fashioned and never ___________ his style. (vary)62. Tom and Tim are twins, but they have different _______________. (person)63. He was one of the ____________ artists of his time. (lead)64. We can use sound effects of add ____________. (exciting)65. For _____________, some comic strips have no frame borders. (vary)66. The young man was lucky enough to be still ____________ after the accident. (living)IV. Rewrite the sentences as required67. If she doesn’t come on time, we’ll go without her. (保持原意)We’ll go without her _____________ she _____________ on time.68. The boy was too frightened to say a word. (保持原意)The boy was __________ frightened that he __________ say a word.69. The coat cost Mary nearly a month salary, ___________ ___________? (反义疑问句)70. He was so fat that he couldn’t get through the door. (保持原意)He was not _________ ___________ to get through the door.71. Did the policemen catch the robber? (改被动语态)____________ the robber ____________ by the policemen?72. Noise pollution makes people talk more loudly than before. (保持原意)People have __________ talk more loudly than before ___________ of noise pollution.73. “Has Bob been to London?” Tom asked. (改为宾语从句)Tom asked ___________ Bob ___________ been to London.C. Read the passage and fill in the blanks with proper words.Do you love holidays, but hate the increase in weight that follows? You are not alone. Holidays are happy days with p_____86______ and delicious foods. But many people are worried about the weight that comes with these delicious foods.With proper planning, it is possible to c______87_____ your weight. The idea is to enjoy the holidays but not to eat too much. You don’t have to turn away from the foods that you enjoy. The following advice may be of some help to you.Do not m______88_____ meals. Before you leave home for a party, have a small, low-fat meal or fast food. This may help to keep you from getting too excited before the wonderful foods.Begin with clear soup and fruit or vegetables. A large glass of water before you eat may help you feel full. Use a small plate; a large plate may make you eat m______89______ than enough. Better not have high-fat foods. Choose lean(瘦的) meats. Fill your plate with salad and green vegetables.Try mints (薄荷) and fruits i______90____ you have a sweet tooth. They do not have fat l_____91_____ cream and chocolate.Don’t let exercise take a b______92______ during the holidays. A 20-minute walk after a meal can help you burn off excess calories. (多余的热量)D. Answer the questions (根据短文内容回答下列问题）No matter what happens, I 'll always be there for youIn 1989 an 8.2 earthquake almost flattened America, killing over 30,000 people in less than four minutes. In the midst of utter devastation and chaos, a father left his wife safely at home and rushed to the school where his son was supposed to be, only to discover that the building was as flat as a pancake.After the unforgettably initial shock, he remembered the promise he had made to his son: "No matter what, I'll always be there for you!" And tears began to fill his eyes. As he looked at the pile of ruins that once was the school, it looked hopeless, but he kept remembering his commitment to his son.He began to direct his attention towards where he walked his son to class at school each morning. Remembering his son's classroom would be in the back right corner of the building, he rushed there and started digging through the ruins.As he was digging, other helpless parents arrived, clutching their hearts, saying: "My son!" "My daughter!" Other well-meaning parents tried to pull him off what was left of the school, saying: "It's too late! They're all dead! You can't help! Go home! Come on, face reality, there's nothing you can do!"To each parent he responded with one line: "Are you going to help me now?" And then hecontinued to dig for his son, stone by stone. The fire chief showed up and tried to pull him off the school's ruins saying, "Fires are breaking out, explosions are happening everywhere. You're in danger. We'll take care of it. Go home." To which this loving, caring American father asked, "Are you going to help me now?"The police came and said, "You're angry, anxious and it's over. You're endangering others. Go home. We'll handle it!" To which he replied, "Are you going to help me now?" No one helped. Courageously he went on alone because he needed to know for himself: "Is my boy alive or is he dead?" He dug for eight hours...12 hours...24 hours...36 hours...then, in the 38th hour, he pulled back a large stone and heard his son's voice. He screamed his son's name, "ARMAND!" He heard back, "Dad!?! It's me, Dad! I told the other kids not to worry. I told them that if you were alive, you'd save me and when you saved me, they'd be saved. You promised, No matter what happens, you'll always be there for you! You did it, Dad!" "What's going on in there? How is it?" the father asked."There are 14 of us left out of 33, Dad. We're scared, hungry, thirsty and thankful you're here. When the building collapsed, it made a triangle, and it saved us.""Come out, boy!""No, Dad! Let the other kids out first, cause I know you'll get me! No matter what happens, I know you'll always be there for me!"93.No one knew what would happen,did they ?_______________________________________________94.How many people lost their lives in the Earthquake in less than four minutes?________________________________________________95.Why was the father so insistent that he kept looking for his son ?_______________________________________________96.All of the parents were looking for their children,weren’t they ?_________________________________________________97.What do you think of the story ?__________________________________________________98.How do you feel about the story ?_________________________________________________首字母附加篇The world p_______is growing very fast. In the last 40 years ,it has doubled . By the year 2200, it will be about 10 billion. Our cities will be much bigger. There will be more factories and more roads. We will need more water and other natural r_______. Therefore, we will have serious problems in the future, so we must change the way we use e_______and natural resources now.Every day we throw away millions of tons of rubbish. Half of this is paper that we can use again. An a_______family in Europe or America throws away more than one ton of rubbish each year, but we can r______much of it. If we recycle things, we can save money,energy and resources. A lot of rubbish, however,cannot be recycled. P________and chemicals will not disappear for hundreds of years. They pollute the air, the land and the water. Pollution will be an even bigger problem in the future. Therefore, we must stop using m_______like plastics and chemicals. Many natural resources cannot be r_______. Coal and minerals, for example, will be used up some day. Other resources take a long time to grow, such as trees, or they may not always be a______, such as water. We must learn to use less energy and fewer resources. We also have to find other w_______to make energy . We can find ways to use the sun, the wind and the sea.KeysI. A C B C C D C B B C B B C A D C A C B DII. C G I F E A B HIII. scenic saying varies personalities leading excitement variety aliveIV. unless comes so couldn’t didn’t it thin enough was caught to because if hadC篇pleasant control miss more if like breakD篇93.No,they didn’t94.Over 30000 people95.Because he made the promise to his son that no matter what ,he would always be there for him.96.No ,they weren’t97.it’s moving98.He is a brave boy附加篇：Population resources energy average reducePlastics materials renewable available ways。
上海西南模范中学中考化学模拟试题_图文
上海西南模范中学中考化学模拟试题_图文一、选择题1．下列四个图像反映了对应实验过程中相关量的变化，其中错误的是A．部分变质的NaOH溶液中滴加稀盐酸B．HCl气体的溶解度受温度影响的变化曲线C．等质量的Mg粉和Fe粉A．A B．B C．C D．D2．下列各组物质的溶液，不用其他试剂没，仅通过观察和用组内溶液相互混合的方法，不能将其逐一鉴别出来的是（）A．NaOH Ca（OH）2HCl Na2CO3B．KCl Ba（NO3）2CuSO4NaOHC．AgNO3HCl Na2CO3CaCl2D．Ba（OH）2KCl Na2SO4Na2CO33．相同质量的M、N两种金属，分别与相同质量分数的足量稀盐酸反应（M、N在生成物中均为+2价），生成H2质量和反应时间的关系如图所示．下列有关叙述正确的是A．金属活动性：N＞M B．生成H2的质量相等C．相对原子质量：N＞M D．消耗盐酸的质量相等4．t℃时，Na2CO3溶解度为Ag，现有饱和Na2CO3溶液(100+A)g，溶质质量分数为a%，向该溶液中投入无水碳酸钠Ag，静置后析出碳酸钠晶体(Na2CO3·10H2O)Bg，加水使晶体全部溶解，所得溶液质量分数为a%，则加入水的质量为( )A．(100+A)g B．100gC．100180286Ag D．(10 -A·a%)g5．正确规范的操作是实验成功和人身安全的重要保证。
下列实验操作正确的是（）A．测定溶液pH B．配制溶液C．称量固体D．稀释浓硫酸6．下表物质中含有少量杂质，其中除杂方法正确的是物质杂质除去杂质的方法A CaCl2溶液HCl滴入碳酸钠溶液B CO2O2通过灼热的铜网C NaOH Na2CO3加入稀盐酸至不再产生气泡D CuO Cu加足量稀盐酸，充分搅拌后再过滤A．A B．B C．C D．D7．在硝酸银、硝酸铜的混合溶液中加入一定量锌粉，反应停止后过滤，滤液仍为蓝色，有关判断正确的是（）A．滤渣中一定有银、没有铜和锌B．滤渣中一定有银和锌，可能有铜C．滤液中一定有硝酸锌、硝酸铜、硝酸银D．滤液中一定有硝酸锌、硝酸铜，可能有硝酸银8．（2012年山东烟台，18题，2分）电影《黄金大劫案》上映后，里面用“王水”（浓盐酸与浓硝酸的混合液）溶解黄金的情引起了广泛的热议。
上海西南模范中学中考物理模拟试题_图文
上海西南模范中学中考物理模拟试题_图文一、选择题1．如图所示，甲、乙两个圆柱形容器中分别装有深度相同、密度不同的液体，静止在水平桌面上。
甲容器的底面积为S1，乙容器的底面积为S2；甲容器中液体的密度为ρ1，液体对容器底产生的压力为F1、压强为p1；乙容器中液体的密度为ρ2，液体对容器底压力为F2、压强为p2。
已知3S1=5S2，2ρ1=ρ2。
则下列叙述中正确的是（）A．F1＞F2，p1＜p2B．F1= F2，p1＜p2C．F1＜F2，p1＜p2D．F1＜F2，p1＞p2 2．某大学两位研究生从蚂蚁身上得到启示，设计出如图所示的“都市蚂蚁”概念车．这款概念车小巧实用，有利于缓解城市交通拥堵．下列关于正在城市中心马路上行驶的此车说法正确的是（）A．以路面为参照物，车是静止的B．以路旁的树木为参照物，车是静止的C．以路旁的房屋为参照物，车是运动的D．以车内的驾驶员为参照物，车是运动的3．地磁场被称为地球生命的“保护伞”。
如图从太阳向其他星体发射出来的高速带电粒子流，在接近地球时，地磁场会改变其运动方向，使其偏离地球，对地球起到了保护作用，以下各图与其原理相同的是（）A．B．C．D．4．小明同学到南美洲游学，见到一种外表酷似微型西瓜的野生水果，其独特的迷你造型和清爽的口感令人称奇．图是迷你“西瓜”与一元硬币放在起的对比照，根据图片信息，估测该迷你“西瓜”的长度约A．2mm B．2cm C．6mm D．6cm5．家庭常用的电吹风既能吹冷风又能吹热风．下列电路中最符合电吹风工作要求的是（）A．B．C．D．6．古代有很多励志故事激励着我们奋发向上，为中华民族的伟大复兴而努力。
关于这些故事中包含的物理道理，下列说法不正确的是（）A．祖逖“闻鸡起舞”，鸡的鸣叫声催人起床说明声音可以传递信息B．项羽“破釜沉舟”，船在下沉过程中所受浮力大于重力C．勾践“卧薪尝胆”，躺在柴薪上通过减小受力面积的方法增大了压强D．匡衡“凿壁偷光”，隔壁的灯光照在书本上发生了漫反射7．在图所示的电路中，电源电压保持不变，现将一个电压表V接入电路的AB或CD两点间．电键 S闭合后，在向左移动滑动变阻器R2滑片P的过程中，下列数值一定不变的是A．电压表 V 的示数B．电流表 A 的示数C．电压表 V 示数与电流表A示数的比值D．电压表 V 示数变化量与电流表 A 示数变化量的比值8．如图是国内首个不用人为控制且能送货到家的无人快递车。
上海西南模范中学九年级上册压轴题数学模拟试卷含详细答案
上海西南模范中学九年级上册压轴题数学模拟试卷含详细答案一、压轴题1．⊙O 是四边形ABCD 的外接圆，OB AC ⊥，OB 与AC 相交于点H ，21012BC AC CD ===，．（1）求⊙O 的半径；（2）求AD 的长；（3）若E 为弦CD 上的一个动点，过点E 作EF//AC ，EG//AD ． EF 与AD 相交于点F ，EG 与AC 相交于点G ．试问四边形AGEF 的面积是否存在最大值？若存在，求出最大面积；若不存在，请说明理由．2．定义：对于二次函数2y ax bx c =++(0)a ≠，我们称函数221()1111()222ax bx c x m y ax bx c x m ⎧++-≥⎪=⎨---+<⎪⎩为它的m 分函数（其中m 为常数）．例如：2y x 的m 分函数为221()11()2x x m y x x m ⎧-≥⎪=⎨-+<⎪⎩．设二次函数244y x mx m =-+的m 分函数的图象为G ．（1）直接写出图象G 对应的函数关系式．（2）当1m =时，求图象G 在14x -≤≤范围内的最高点和最低点的坐标．（3）当图象G 在x m ≥的部分与x 轴只有一个交点时，求m 的取值范围．（4）当0m >，图象G 到x 轴的距离为m 个单位的点有三个时，直接写出m 的取值范围．3．已知：如图，抛物线2134y x x =--交x 正半轴交于点A ，交y 轴于点B ，点()4,C n -在抛物线上，直线l ：34y x m =-+过点B ，点E 是直线l 上的一个动点，ACE △的外心是P ．（1）求m，n的值．△的面积．（2）当点E移动到点B时，求ACE△的边上，若存在，求出点E的坐标，若不（3）①是否存在点E，使得点P落在ACE存在，请说明理由．轴交直线l于点D，当点E从点D移动到点B时，圆心P移动的②过点A作直线AD x路线长为_____．（直接写出答案）4．在平面直角坐标系中，抛物线y＝ax2+bx﹣3过点A（﹣3，0），B（1，0），与y轴交于点C，顶点为点D．（1）求抛物线的解析式；（2）点P为直线CD上的一个动点，连接BC；①如图1，是否存在点P，使∠PBC＝∠BCO？若存在，求出所有满足条件的点P的坐标；若不存在，请说明理由；②如图2，点P在x轴上方，连接PA交抛物线于点N，∠PAB＝∠BCO，点M在第三象限抛物线上，连接MN，当∠ANM＝45°时，请直接写出点M的坐标．5．如图，A是以BC为直径的圆O上一点，AD⊥BC于点D，过点B作圆O的切线，与CA 的延长线相交于点E，G是AD的中点，连接并延长CG与BE相交于点F，连接并延长AF与CB的延长线相交于点P．（1）求证：BF＝EF；（2）求证：PA是圆O的切线；（3）若FG＝EF＝3，求圆O的半径和BD的长度．6．如图①是一张矩形纸片，按以下步骤进行操作：(Ⅰ)将矩形纸片沿DF折叠，使点A落在CD边上点E处，如图②；(Ⅱ)在第一次折叠的基础上，过点C再次折叠，使得点B落在边CD上点B′处，如图③，两次折痕交于点O；(Ⅲ)展开纸片，分别连接OB、OE、OC、FD，如图④．（探究）（1）证明：OBC≌OED；（2）若AB＝8，设BC为x，OB2为y，是否存在x使得y有最小值，若存在求出x的值并求出y的最小值，若不存在，请说明理由．7．四边形ABCF中，AF∥BC，∠AFC=90°，△ABC的外接圆⊙O交CF于E，与AF相切于点A，过C作CD⊥AB于D，交BE于G．（1）求证：AB=AC；（2）①证明：GE=EC；②若BC=8，OG=1，求EF的长．8．（问题发现）（1）如图①，在△ABC中，AC＝BC＝2，∠ACB＝90°，D是BC边的中点，E是AB边上一动点，则EC+ED的最小值是．（问题研究）（2）如图②，平面直角坐标系中，分别以点A（﹣2，3），B（3，4）为圆心，以1、3为半径作⊙A、⊙B，M、N分別是⊙A、⊙B上的动点，点P为x轴上的动点，试求PM+PN的最小值．（问题解决）（3）如图③，该图是某机器零件钢构件的模板，其外形是一个五边形，根据设计要求，边框AB 长为2米，边框BC 长为3米，∠DAB ＝∠B ＝∠C ＝90°，联动杆DE 长为2米，联动杆DE 的两端D 、E 允许在AD 、CE 所在直线上滑动，点G 恰好是DE 的中点，点F 可在边框BC 上自由滑动，请确定该装置中的两根连接杆AF 与FG 长度和的最小值并说明理由．9．定义：对于已知的两个函数，任取自变量x 的一个值，当0x ≥时，它们对应的函数值相等；当0x <时，它们对应的函数值互为相反数，我们称这样的两个函数互为相关函数.例如：正比例函数y x =，它的相关函数为(0)(0)x x y x x ≥⎧=⎨-<⎩. （1）已知点()5,10A -在一次函数5y ax =-的相关函数的图像上，求a 的值；（2）已知二次函数2142y x x =-+-. ①当点3,2B m ⎛⎫ ⎪⎝⎭在这个函数的相关函数的图像上时，求m 的值； ②当33x -≤≤时，求函数2142y x x =-+-的相关函数的最大值和最小值. （3）在平面直角坐标系中，点M 、N 的坐标分别为1,12⎛⎫- ⎪⎝⎭、9,12⎛⎫ ⎪⎝⎭，连结MN .直接写出线段MN 与二次函数24y x x n =-++的相关函数的图像有两个公共点时n 的取值范围.10．公司经销某种商品，经研究发现，这种商品在未来40天的销售单价1y （元/千克）关于时间t 的函数关系式分别为11602y t =-+（040t <≤，且t 为整数）； ()()21030,3033040,20t t t y t t ⎧<≤-+⎪=⎨<≤⎪⎩且为整数且为整数，他们的图像如图1所示，未来40天的销售量m （千克）关于时间t 的函数关系如图2的点列所示．（1）求m 关于t 的函数关系式；（2）那一天的销售利润最大，最大利润是多少？（3）若在最后10天，公司决定每销售1千克产品就捐赠a 元给“环保公益项目”，且希望扣除捐赠后每日的利润不低于3600元以维持各种开支，求a 的最大值（精确到0.01元）．11．如图，在ABCD 中，E 为边BC 的中点，F 为线段AE 上一点，连结BF 并延长交边AD 于点G ，过点G 作AE 的平行线，交射线DC 于点H ，设AD EF x AB AF==．（1）当1x =时，求:AG AB 的值；（2）设GDH EBAS y S =△△，求y 关于x 的函数关系式； （3）当3DH HC =时，求x 的值．12．如图1，梯形ABCD 中，AD ∥BC ，AB=AD=DC=5，BC=11．一个动点P 从点B 出发，以每秒1个单位长度的速度沿线段BC 方向运动，过点P 作PQ ⊥BC ，交折线段BA-AD 于点Q ，以PQ 为边向右作正方形PQMN ，点N 在射线BC 上，当Q 点到达D 点时，运动结束．设点P 的运动时间为t 秒（t ＞0）．（1）当正方形PQMN 的边MN 恰好经过点D 时，求运动时间t 的值；（2）在整个运动过程中，设正方形PQMN 与△BCD 的重合部分面积为S ，请直接写出S 与t 之间的函数关系式和相应的自变量t 的取值范围；（3）如图2，当点Q 在线段AD 上运动时，线段PQ 与对角线BD 交于点E ，将△DEQ 沿BD 翻折，得到△DEF ，连接PF ．是否存在这样的t ，使△PEF 是等腰三角形？若存在，求出对应的t 的值；若不存在，请说明理由．13．在锐角△ABC中，AB=AC，AD为BC边上的高，E为AC中点．（1）如图1，过点C作CF⊥AB于F点，连接EF．若∠BAD=20°，求∠AFE的度数；（2）若M为线段BD上的动点（点M与点D不重合），过点C作CN⊥AM于N点，射线EN，AB交于P点．①依题意将图2补全；②小宇通过观察、实验，提出猜想：在点M运动的过程中，始终有∠APE=2∠MAD．小宇把这个猜想与同学们进行讨论，形成了证明该猜想的几种想法：想法1：连接DE，要证∠APE=2∠MAD，只需证∠PED=2∠MAD．想法2：设∠MAD=α，∠DAC=β，只需用α，β表示出∠PEC，通过角度计算得∠APE=2α．想法3：在NE上取点Q，使∠NAQ=2∠MAD，要证∠APE=2∠MAD，只需证△NAQ∽△APQ．……请你参考上面的想法，帮助小宇证明∠APE=2∠MAD．（一种方法即可）14．如图，正方形ABCD中，对角线AC、BD交于点O，E为OC上动点(与点O不重合)，作AF⊥BE，垂足为G，交BO于H．连接OG、CG．(1)求证：AH=BE；(2)试探究：∠AGO 的度数是否为定值？请说明理由；(3)若OG⊥CG，BG=32△OGC的面积．15．在直角坐标平面内，O为原点，点A的坐标为(10)，，点C的坐标为(0)4，，直线CM x∥轴（如图所示）．点B与点A关于原点对称，直线y x b=+（b为常数）经过点B，且与直线CM相交于点D，联结OD．（1）求b的值和点D的坐标；（2）设点P在x轴的正半轴上，若POD是等腰三角形，求点P的坐标；16．如图，在平面直角坐标系xOy中，直线y＝12x+2与x轴交于点A，与y轴交于点C．抛物线y＝ax2+bx+c的对称轴是x＝32-且经过A、C两点，与x轴的另一交点为点B．（1）求抛物线解析式．（2）若点P为直线AC上方的抛物线上的一点，连接PA，PC．求△PAC的面积的最大值，并求出此时点P的坐标．（3）抛物线上是否存在点M，过点M作MN垂直x轴于点N，使得以点A、M、N为顶点的三角形与△ABC相似？若存在，求出点M的坐标；若不存在，请说明理由．17．如图，在平面直角坐标系中，以原点O为中心的正方形ABCD的边长为4m，我们把AB y∥轴时正方形ABCD的位置作为起始位置，若将它绕点O顺时针旋转任意角度α时，它能够与反比例函数(0)k y k x =>的图象相交于点E ，F ，G ，H ，则曲线段EF ，HG 与线段EH ，GF 围成的封闭图形命名为“曲边四边形EFGH”．（1）①如图1，当AB y ∥轴时，用含m ，k 的代数式表示点E 的坐标为________；此时存在曲边四边形EFGH ，则k 的取值范围是________；②已知23k m =，把图1中的正方形ABCD 绕点O 顺时针旋转45º时，是否存在曲边四边形EFGH ？请在备用图中画出图形，并说明理由．当把图1中的正方形ABCD 绕点O 顺时针旋转任意角度α时，直接写出使曲边四边EFGH 存在的k 的取值范围．③若将图1中的正方形绕点O 顺时针旋转角度()0180a a ︒<<︒得到曲边四边形EFGH ，根据正方形和双曲线的对称性试探究四边形EFGH 是什么形状的四边形？曲边四边形EFGH 是怎样的对称图形？直接写出结果，不必证明；（2）正方形ABCD 绕点O 顺时针旋转到如图2位置，已知点A 在反比例函数(0)k y k x=>的图象上，AB 与y 轴交于点M ，8AB =，1AM =，试问此时曲边四边EFGH 存在吗？请说明理由．18．如图，在直角坐标系中，点C 在第一象限，CB x ⊥轴于B ，CA y ⊥轴于A ，3CB =，6CA =，有一反比例函数图象刚好过点C ．（1）分别求出过点C 的反比例函数和过A ，B 两点的一次函数的函数表达式；（2）直线l x ⊥轴，并从y 轴出发，以每秒1个单位长度的速度向x 轴正方向运动，交反比例函数图象于点D ，交AC 于点E ，交直线AB 于点F ，当直线l 运动到经过点B 时，停止运动．设运动时间为t （秒）．①问：是否存在t 的值，使四边形DFBC 为平行四边形？若存在，求出t 的值；若不存在，说明理由；②若直线l从y轴出发的同时，有一动点Q从点B出发，沿射线BC方向，以每秒3个单位长度的速度运动．是否存在t的值，使以点D，E，Q，C为顶点的四边形为平行四边形；若存在，求出t的值，并进一步探究此时的四边形是否为特殊的平行四边形；若不存在，说明理由．19．如图，在矩形ABCD中，已知AB=4，BC=2，E为AB的中点，设点P是∠DAB平分线上的一个动点（不与点A重合）．（1）证明：PD=PE．（2）连接PC，求PC的最小值．（3）设点O是矩形ABCD的对称中心，是否存在点P，使∠DPO=90°？若存在，请直接写出AP的长．20．如图，⊙O经过菱形ABCD的三个顶点A、C、D，且与AB相切于点A．（1）求证：BC为⊙O的切线；（2）求∠B的度数．（3）若⊙O半径是4，点E是弧AC上的一个动点，过点E作EM⊥OA于点M，作EN⊥OC 于点N，连接MN，问：在点E从点A运动到点C的过程中，MN的大小是否发生变化？如果不变化，请求出MN的值；如果变化，请说明理由．【参考答案】***试卷处理标记，请不要删除一、压轴题1．（1）⊙O的半径为10，（2）AD长为19.2，（3）存在，四边形AGEF的面积的最大值为34.56．【解析】【分析】（1）如图1利用垂径定理构造直角三角形解决问题．（2）如图2在（1）基础上利用圆周角和圆心角的关系证明△OCH∽△DCK，求出Dk，再据垂径定理求得AD．（3）如图3以平行四边形AGEF的面积为函数，以AG边上的高为自变量，列出一个二次函数，利用二次函数的最值求解．【详解】（1）如图1连接OC ，因为OB AC ⊥,根据垂径定理知 HC=1112622AC =⨯= 在RT △BCH 中 ∵210BC = ∴由勾股定理知：2222BH (210)62BC HC =-=-=∴OH=OB-BH=OB-2 又∵OB=OC所以在RT △OCH 中，由勾股定理可得方程：2222)6OC OC -+=（ 解得OC=10．（2）如图2，在⊙O 中：∵AC=CD ，∴OC ⊥AD （垂径定理） ∴AD=2KD ，∠HCK=∠DCK 又∵∠DKC=∠OHC=90° ∴△OCH ∽△DCK ∴KD DC HO OC= ∴DC 1248KD=8105HO OC =⨯==9.6 ∴AD=2KD=19.2．（3）如图3本题与⊙O 无关，但要运用前面数据．作FM ⊥AC 于M ，作DN ⊥AC 于N ，显然四边形AGEF 为平行四边形，设平行四边形AGEF 的面积为y 、EM=x 、DN=a （a 为常量）， 先运用(2)的△OCH ∽△DCK ，得CK=7.2． 易得△DFE ∽△DAC ， ∴DN-EM EFDN AC =（相似三角形对应高之比等于相似比） ∴DN EMAG=EF=AC DN- ∴AG=12()aa x - ∴平行四边形AGEF 的面积y=212()1212a x x x x a a -=-+(0＜x ＜a ） 由二次函数知识得，当x=12a1222a-=-⨯时，y 有最大值． 把x=2a 代入到中得，12EF AC = ∴此时EF 、EG 、FG 恰是△ADC 的中位线 ∴四边形AGEF 的面积y 最大=111S 34.56222ADC AD CK ∆=⨯⨯=． 【点睛】本题主要考查与圆有关线段的计算、与二次函数有关的几何最值问题．（1）的关键是利用垂径定理构造直角三角形，最后用勾股定理进行计算．（2）的关键是运用与圆有的角的性质证明相似，再进行计算．（3）难点是分清图形的变与不变，选择恰当的变量并列出函数关系式．2．（1）22441()1221()2x mx m x m y x mx m x m ⎧-+-≥⎪=⎨-+-+<⎪⎩（2）图象G 在14x -≤≤范围内的最高点和最低点的坐标分别为(4,3)，71,2⎛⎫-- ⎪⎝⎭（3）当13m <或12m =或1m 时，图象G 在x m ≥的部分与x 轴只有一个交点（4）5363m +<<，1343m <<．【解析】 【分析】（1）根据分函数的定义直角写成关系式即可；（2）将m=1代入（1）所得的分函数可得2243(1)121(1)2x x x y x x x ⎧-+≥⎪=⎨-+-<⎪⎩，然后分11x -≤<和14x ≤≤两种情况分别求出最高点和最低点的坐标，最后比较最大值和最小值即可解答；（3）由于图象G 在x m ≥的部分与x 轴只有一个交点时，则可令对应二元一次方程的根的判别式等于0，即可确定m 的取值；同时发现无论m 取何实数、该函数的图象与x 轴总有交点，再令x=m 代入原函数解析式，求出m 的值，据此求出m 的取值范围； （4）先令2441x mx m m -+-=或-m①，利用根的判别式小于零确定求出m 的取值范围，然后再令x=m 代入2441x mx m m -+-=或-m②，然后再令判别式小于零求出m 的取值范围，令x=m 代入212212x mx m m -+-+=或-m③，令判别式小于零求出m 的范围，然后取①②③两两的共同部分即为m 的取值范围． 【详解】（1）图象G 对应的函数关系式为22441()1221()2x mx m x m y x mx m x m ⎧-+-≥⎪=⎨-+-+<⎪⎩（2）当1m =时，图象G 对应的函数关系式为2243(1)121(1)2x x x y x x x ⎧-+≥⎪=⎨-+-<⎪⎩．当11x -≤<时，将21212y x x =-+-配方，得21(2)12y x =--+． 所以函数值y 随自变量x 的增大而增大，此时函数有最小值，无最大值． 所以当1x =-时，函数值y 取得最小值，最小值为72y =-． 所以最低点的坐标为71,2⎛⎫-- ⎪⎝⎭． 当14x ≤≤时，将243y xx =-+配方，得2(2)1y x =--．所以当2x =时，函数值y 取得最小值，最小值为1y =- 所以当4x =时，函数值y 取得最大值，最大值为3y =所以最低点的坐标为(2,1)-，最高点的坐标为(4,3)所以，图象G 在14x -≤≤范围内的最高点和最低点的坐标分别为(4,3)，71,2⎛⎫-- ⎪⎝⎭． （3）当x m ≥时，令0y =，则24410x mx m -+-=2(4)4(41)m m ∆=-- 24(21)m =-所以无论m 取何实数，该函数的图象与x 轴总有交点． 所以当12m =时，图象G 在12x ≥的部分与x 轴只有一个交点． 当x m =时，222441341y m m m m m =-+-=-+-． 令0y =，则23410m m -+-=． 解得113m =，21m =． 所以当13m <或1m 时，图象G 在x m ≥的部分与x 轴只有一个交点．综上所述，当13m <或12m =或1m 时，图象G 在x m ≥的部分与x 轴只有一个交点．（4）当2441x mx m m -+-=即24310x mx m -+-=， △=()()22443116124m m m m --=-+＞0，方∵212416452<0-⨯⨯=-， ∴m 不存在；当2441x mx m m -+-=-即24510x mx m -+-=， △=()()22445116204m m m m --=-+＜0，解得14＜m ＜1；① 将x=m 代入2441>x mx m m -+-得-3m 2+3m-1＞0，因△=()()234133<0-⨯--=-则m 不存在；将x=-m 代入2441>x mx m m -+-得-3m 2+5m-1＞0， 解得m 或m ；②将x=m 代入212212x mx m m -+-+=得 221023<m m -+，解得m <或33m +<③ 将x=m 代入212212x mx m m -+-+=-得 21=023m m -+，因△=23145<02-⨯=-故m 不存在；在①②③m <14m <<，即为图象G 到x 轴的距离为m 个单位的点有三个时的m 的取值范围． 【点睛】本题属于二次函数综合题，考查了新定义函数的定义、二次函数最值和二次函数图像，正确运用二次函数图像的性质和分类讨论思想是解答本题的关键． 3．（1）3,5m n =-=；（2）30ACES=；（3）①点E 的坐标为：1653,1122⎛⎫-- ⎪⎝⎭或6415,1111E ⎛⎫- ⎪⎝⎭或3660,1111E ⎛⎫- ⎪⎝⎭； ②圆心P 移动的路线长 【解析】 【分析】 （1）令2130,4y x x =--=求出点A （6，0），把点C （-4，n ）代入在抛物线方程，解得：n=5，把点B （0，-3）代入34y x m =-+，从而可得答案；（2）记AC 与y 轴的交点为H ，利用()1.2ACEA C SBH x x =••-即可求解； （3）①分当点P 落在CA 上时，点P 落在AE 上时，点P 落在CE 上时三种情况讨论即可； ②分E 在D 和B 点两种情况，求出圆心12,P P 点的坐标，则圆心P 移动的路线长=12PP ，即可求解． 【详解】 解：（1）令2130,4y x x =--= 24120,x x ∴--=()()260,x x ∴+-= 122,6,x x ∴=-=∴ 点A （6，0），把点C （-4，n ）代入在抛物线方程， 解得：()()214435,4n =⨯----= ()4,5C ∴-，把点B （0，-3）代入34y x m =-+，解得：3m =-， 则：直线l ：334y x =--，…①3,5,m n ∴=-=（2）由（1）知：A （6，0）、B （0，-3）、C （-4，5）、 AC 中点为51,,2⎛⎫⎪⎝⎭设AC 为：,y kx b =+6045k b k b +=⎧∴⎨-+=⎩解得：123k b ⎧=-⎪⎨⎪=⎩AC ∴所在的直线方程为：132y x =-+， 如图，AC 与y 轴交点H 坐标为：（0，3），()1161030.22ACEA C SBH x x ∴=••-=⨯⨯=（3）如下图： ①当点P 落在CA 上时， 圆心P 为AC 的中点51,,2⎛⎫⎪⎝⎭其所在的直线与AC 垂直，1,2AC k =-AC ∴的垂直平分线即圆心P 所在的直线方程为：2,y x a =+把51,2⎛⎫ ⎪⎝⎭代入得：52,2a =+ 1,2a ∴=122y x ∴=+…②，334122y x y x ⎧=--⎪⎪∴⎨⎪=+⎪⎩①②解得：1611,5322x y ⎧=-⎪⎪⎨⎪=-⎪⎩E 的坐标为1653,1122⎛⎫-- ⎪⎝⎭； 当点P 落在AE 上时， 设点3,3,4E m m ⎛⎫-- ⎪⎝⎭则点P 的坐标633,282m m +⎛⎫-- ⎪⎝⎭， 则PA=PC ，2222633633645282282m m m m ++⎛⎫⎛⎫⎛⎫⎛⎫∴-++=++++ ⎪ ⎪ ⎪ ⎪⎝⎭⎝⎭⎝⎭⎝⎭解得：64,11m =-故点6415,.1111E ⎛⎫-⎪⎝⎭当点P 落在CE 上时， 则PC=PA ， 同理可得：36,11m = 故点3660,1111E ⎛⎫-⎪⎝⎭综上，点E 的坐标为：1653,1122⎛⎫-- ⎪⎝⎭或6415,1111E ⎛⎫- ⎪⎝⎭或3660,1111E ⎛⎫- ⎪⎝⎭；②当E 在D 点时，作AD 的垂直平分线交AC 的垂直平分线于1P 点， 则156,2D ⎛⎫-⎪⎝⎭，1P 的纵坐标为15,4- 代入②式，解得：11715,,84P ⎛⎫-- ⎪⎝⎭ 同理当当E 在B 点时， 作AB 的垂直平分线交AC 的垂直平分线于2P 点，()()6,0,0,3,A B -AB ∴的中点为：33,2⎛⎫- ⎪⎝⎭，设AB 为：y ex f =+，603e f f +=⎧∴⎨=-⎩解得：123e f ⎧=⎪⎨⎪=-⎩∴ AB 直线方程为：132y x =-， 设AB 的垂直平分线方程为：12,y x b =-+1323,2b ∴-⨯+=-192b ∴=， ∴ AB 的垂直平分线方程为：92,2y x =-+122922y x y x ⎧=+⎪⎪∴⎨⎪=-+⎪⎩解得：152x y =⎧⎪⎨=⎪⎩251,,2P ⎛⎫∴ ⎪⎝⎭则圆心P 移动的路线长=12PP ==故答案为：255 8【点评】本题是二次函数的综合题，考查了二次函数与x轴的交点坐标，利用待定系数法求解一次函数的解析式，三角形的外心的性质、一次函数的交点问题，勾股定理的应用，综合性很强，是难度较大类题目．4．（1）y＝x2+2x﹣3；（2）①存在，点P的坐标为（1，﹣2）或（﹣5，﹣8）；②点M（﹣43，﹣359）【解析】【分析】（1）y＝ax2+bx﹣3＝a（x+3）（x﹣1），即可求解；（2）①分点P（P′）在点C的右侧、点P在点C的左侧两种情况，分别求解即可；②证明△AGR≌△RHM（AAS），则点M（m+n，n﹣m﹣3），利用点M在抛物线上和AR ＝NR，列出等式即可求解．【详解】解：（1）y＝ax2+bx﹣3＝a（x+3）（x﹣1），解得：a＝1，故抛物线的表达式为：y＝x2+2x﹣3①；（2）由抛物线的表达式知，点C、D的坐标分别为（0，﹣3）、（﹣1，﹣4），由点C、D的坐标知，直线CD的表达式为：y＝x﹣3；tan∠BCO＝13，则cos∠BCO10①当点P（P′）在点C的右侧时，∵∠P′AB＝∠BCO，故P′B∥y轴，则点P′（1，﹣2）；当点P在点C的左侧时，设直线PB交y轴于点H，过点H作HN⊥BC于点N，∵∠PBC＝∠BCO，∴△BCH为等腰三角形，则BC＝2CH•cos∠BCO＝2×CH1022 3110 +解得：CH＝53，则OH＝3﹣CH＝43，故点H（0，﹣43），由点B、H的坐标得，直线BH的表达式为：y＝43x﹣43②，联立①②并解得：58 xy=-⎧⎨=-⎩，故点P的坐标为（1，﹣2）或（﹣5，﹣8）；②∵∠PAB＝∠BCO，而tan∠BCO＝13，故设直线AP的表达式为：y＝13x s+，将点A的坐标代入上式并解得：s＝1，故直线AP的表达式为：y＝13x+1，联立①③并解得：43139xy⎧=⎪⎪⎨⎪=⎪⎩，故点N（43，139）；设△AMN的外接圆为圆R，当∠ANM＝45°时，则∠ARM＝90°，设圆心R的坐标为（m，n），∵∠GRA+∠MRH＝90°，∠MRH+∠RMH＝90°，∴∠RMH＝∠GAR，∵AR＝MR，∠AGR＝∠RHM＝90°，∴△AGR≌△RHM（AAS），∴AG＝m+3＝RH，RG＝﹣n＝MH，∴点M（m+n，n﹣m﹣3），将点M的坐标代入抛物线表达式得：n﹣m﹣3＝（m+n）2+2（m+n）﹣3③，由题意得：AR＝NR，即（m+3）2＝（m﹣43）2+（139）2④，联立③④并解得：29109mn⎧=-⎪⎪⎨⎪=-⎪⎩，故点M（﹣43，﹣359）．【点睛】本题考查的是二次函数综合运用，涉及到一次函数的性质、三角形全等、圆的基本知识等，其中（2）①，要注意分类求解，避免遗漏．5．（1）详见解析；（2）详见解析；（3）BD＝2r＝2【解析】【分析】（1）根据已知条件得到∠EBC＝∠ADC＝90°，根据平行线分线段成比例定理得出AG CG GD==EF CF BF，等量代换即可得到结论；（2）证明∠PAO＝90°，连接AO，AB，根根据直角三角形斜边中线的性质，切线的性质和等量代换，就可得出结论；（3）连接AB，根据圆周角定理得到∠BAC＝∠BAE＝90°，推出FA＝FB＝FE＝FG＝3，过点F作FH⊥AG交AG于点H，推出四边形FBDH是矩形，得到FB＝DH＝3，根据勾股定理得到FH＝22，设半径为r，根据勾股定理列方程即可得到结论．【详解】解：（1）∵EB是切线，AD⊥BC，∴∠EBC＝∠ADC＝90°，∴AD∥EB，（同位角相等，两直线平行）∴AG CG GD==EF CF BF，（平行线分线段成比例）∵G是AD的中点，∴AG＝GD，∴EF＝FB；（2）证明：连接AO，AB，∵BC是⊙O的直径，∴∠BAC＝90°，（直径所对圆周角为直角）在Rt△BAE中，由（1）知，F是斜边BE的中点，直角三角形斜边中线为斜边一半，∴AF＝FB＝EF，且等边对等角，∴∠FBA＝∠FAB，又∵OA＝OB，∴∠ABO＝∠BAO，∵BE是⊙O的切线，∴∠EBO＝90°，∵∠EBO＝∠FBA+∠ABO＝∠FAB+∠BAO＝∠FAO＝90°，∴PA是⊙O的切线；（3）如图2，连接AB，AO，∵BC是直径，∴∠BAC＝∠BAE＝90°，∵EF＝FB，∴FA＝FB＝FE＝FG＝3，过点F作FH⊥AG交AG于点H，∵FA＝FG，FH⊥AG，∴AH＝HG，∵∠FBD＝∠BDH＝∠FHD＝90°，∴四边形FBDH是矩形，∴FB＝DH＝3，∵AG＝GD，∴AH＝HG＝1，GD＝2，FH，∴BD＝设半径为r，在Rt ADO中，AO=AD+OD，∵222r=4，解得：r＝∴222综上所示：BD＝r＝【点睛】本题主要考察了平行线的性质及定理、平行线分线段成比例定理、等边对等角、直角三角形斜边中线的性质、圆周角定理、勾股定理及圆的切线及其性质，该题较为综合，解题的关键是在于掌握以上这些定理，并熟练地将其结合应用．6．（1）见解析；（2）x=4，16【解析】【分析】（1）连接EF，根据矩形和正方形的判定与性质以及折叠的性质，运用SAS证明OBC≌OED即可；（2）连接EF、BE，再证明△OBE是直角三角形，然后再根据勾股定理得到y与x的函数关系式，最后根据二次函数的性质求最值即可．【详解】（1）证明：连接EF．∵四边形ABCD是矩形，∴AD＝BC，∠ABC＝∠BCD＝∠ADE＝∠DAF＝90°由折叠得∠DEF＝∠DAF，AD＝DE∴∠DEF＝90°又∵∠ADE＝∠DAF＝90°，∴四边形ADEF是矩形又∵AD＝DE，∴四边形ADEF是正方形∴AD＝EF＝DE，∠FDE＝45°∵AD＝BC，∴BC＝DE由折叠得∠BCO＝∠DCO＝45°∴∠BCO ＝∠DCO ＝∠FDE ．∴OC ＝OD ．在△OBC 与△OED 中，BC DE BCO FDE OC OD =⎧⎪∠=∠⎨⎪=⎩，，， ∴△OBC ≌△OED （SAS ）；（2）连接EF 、BE ．∵四边形ABCD 是矩形，∴CD ＝AB ＝8．由（1）知，BC ＝DE∵BC ＝x ，∴DE ＝x∴CE ＝8－x由（1）知△OBC ≌△OED∴OB ＝OE ，∠OED ＝∠OBC ．∵∠OED ＋∠OEC ＝180°，∴∠OBC ＋∠OEC ＝180°．在四边形OBCE 中，∠BCE ＝90°，∠BCE ＋∠OBC ＋∠OEC ＋∠BOE ＝360°，∴∠BOE ＝90°．在Rt △OBE 中，OB 2＋OE 2＝BE 2．在Rt △BCE 中，BC 2＋EC 2＝BE 2．∴OB 2＋OE 2＝BC 2＋CE 2．∵OB 2＝y ，∴y ＋y ＝x 2＋(8－x)2．∴y ＝x 2－8x ＋32∴当x=4时，y 有最小值是16．【点睛】本题是四边形综合题，主要考查了矩形和正方形的判定与性质、折叠的性质、全等三角形的判定、勾股定理以及运用二次函数求最值等知识点，灵活应用所学知识是解答本题的关键．7．（1）见详解；（2）①见详解；②EF=2．【解析】【分析】（1）连接OC ，则OA=OB=OC ，先证明OA ∥FC ，则有∠ACE=∠CAO ，由∠ABE=∠ACE ，然后得到∠AOB=∠AOC ，即可得到结论成立；（2）①先证明BE 是直径，则先证明∠ACD=∠EBC ，由∠ABC=∠ACB ，则∠BCD=∠ABG=∠ACE ，则得到∠EGC=∠ECG ，即可得到GE=EC ；②由①可知，GE=EC=r+1，在直角三角形BCE 中，由勾股定理得222(2)8(1)r r =++，得到半径，然后得到EC 的长度；作OM ⊥CE 于点M ，则EM=3，即可求出EF 的长度．【详解】解：（1）连接OC ，则OA=OB=OC ，∴∠ABO=∠BAO ，∠ACO=∠CAO ，∵AF 是切线，∴∠FAO=90°=∠AFC ，∴OA ∥FC ，∴∠CAO=∠ACE=∠ABO ，∴∠ABO=∠BAO=∠ACO=∠CAO ，∴∠AOB=∠AOC ，∴AB=AC ；（2）①∵AF ∥BC ，∠AFC=90°，∴∠BCE=90°，∴BE 是直径，∵CD ⊥AB ，∴∠DAC+∠ACD=∠BEC+∠EBC ，∵∠DAC=∠BEC ，∴∠ACD=∠EBC ，∵AB=AC ，∴∠ABC=∠ACB ，∴∠ABO+∠EBC=∠ACD+∠BCD ，∴∠ABO=∠BCD=∠ACE ，∴∠EBC+∠BCD=∠ACD+∠ACE ，∴∠EGC=∠ECG ，∴EG=EC ；②作OM ⊥CE 于点M ，如图：则四边形AOMF 是矩形，∴AO=FM ，∵OG=1，设GE=EC=r+1，在Rt △BCE 中，由勾股定理得222BE BC CE =+，∴222(2)8(1)r r =++，解得：=5r （负值已舍去），∴AO=FM=5，EC=6，∵OM ⊥EC ，OM 是半径，EC 是弦， ∴116322EM EC ==⨯=， ∴532EF FM EM =-=-=．【点睛】本题考查了圆的综合问题，切线的性质定理，圆周角定理，勾股定理，垂径定理，以及矩形的性质，同角的余角相等，解题的关键是熟练掌握所学的知识进行解题，注意正确作出辅助线，运用数形结合的思想进行分析．8．（152744；（3）4，理由见解析【解析】【分析】（1）作点C 关于AB 的对称点C '，连接DE ，与AB 交于点E ，连接CE ．此时EC +ED ＝EC '+ED ＝C 'D 最短，易证DBC '＝90°，C 'B ＝CB ＝2，DB ＝1，所以在Rt △DBC '中，C 'D 2＝12+22＝5，故CD 5EC +ED 5（2）作⊙A 关于x 轴的对称⊙A ′，连接BA ′分别交⊙A ′和⊙B '于M '、N ，交x 轴于P ，连接PA ，交⊙A 于M ，根据两点之间线段最短得到此时PM +PN 最小，再利用对称确定A ′的坐标，接着利用两点间的距离公式计算出A ′B 的长，然后用A ′B 的长减去两个圆的半径即可得到MN 的长，即得到PM +PN 的最小值；（3）如图③，延长AD、CE，交于点H，连接GH．易知GE＝12DE＝1，所以点G在以H为圆心，1为半径的圆周上运动，作点A关于BC的对称点A'，连接A'H，与BC交于点F，与⊙H交于点G，此时AF+FG＝A'F+FG＝A'G为最短，AB＝2，AH＝BC＝3，A'B＝2，A'A＝4，所以A'H＝2234=5，因此A'G＝A'H﹣GH＝5﹣1＝4，即该装置中的两根连接杆AF 与FG长度和的最小值为4．【详解】解：（1）如图①，作点C关于AB的对称点C'，连接DE，与AB交于点E，连接CE．∴CE＝C'E，此时EC+ED＝EC'+ED＝C'D最短，∵AC＝BC＝2，∠ACB＝90°∴∠CBA＝∠CAB＝45°，C'B＝CB＝2∴∠C'BA＝45°，∴∠DBC'＝90°∵D是BC边的中点，∴DB＝1，在Rt△DBC'中，C'D2＝12+22＝5，∴CD＝5，∴EC+ED的最小值是5，故答案为5；（2）如图②，作⊙A关于x轴的对称⊙A′，连接BA′分别交⊙A′和⊙B'于M'、N，交x轴于P，连接PA，交⊙A于M．则此时PM +PN ＝PM '+PN ＝M 'N 最小，∵点A 坐标（﹣2，3），∴点A ′坐标（﹣2，﹣3），∵点B （3，4），∴A 'B ＝()()223243+++＝74，∴M 'N ＝A ′B ﹣BN ﹣A ′M '＝74﹣1﹣3＝74﹣4∴PM +PN 的最小值为＝74﹣4；（3）如图③，延长AD 、CE ，交于点H ，连接GH ．∵∠DAB ＝∠B ＝∠C ＝90°∴∠DHE ＝90°，∵G 是DE 的中点，DE ＝2，∴GE ＝12DE ＝1， ∵联动杆DE 的两端D 、E 允许在AD 、CE 所在直线上滑动，∴点G 在以H 为圆心，1为半径的圆周上运动，作点A 关于BC 的对称点A '，连接A 'H ，与BC 交于点F ，与⊙H 交于点G ，此时AF +FG ＝A 'F +FG ＝A 'G 为最短，∵AB ＝2，AH ＝BC ＝3，A 'B ＝2，A 'A ＝4，∴A 'H 2234+，∴A 'G ＝A 'H ﹣GH ＝5﹣1＝4，所以该装置中的两根连接杆AF 与FG 长度和的最小值为4．【点睛】本题考查了圆的综合题，涉及到勾股定理、轴对称性质求最短值，综合性比较强，结合题意添加合适的辅助线是解题的关键．9．（1）1；（2）①2225-；②max 432y =，min 12y =-；（3）31n -<≤-，514n <≤ 【解析】【分析】（1）先求出5y ax =-的相关函数，然后代入求解，即可得到答案；（2）先求出二次函数的相关函数，①分为m ＜0和m ≥0两种情况将点B 的坐标代入对应的关系式求解即可；②当-3≤x ＜0时，y=x 2-4x+12，然后可 此时的最大值和最小值，当0≤x≤3时，函数y=-x 2+4x-12，求得此时的最大值和最小值，从而可得到当-3≤x≤3时的最大值和最小值； （3）首先确定出二次函数y=-x 2+4x+n 的相关函数与线段MN 恰好有1个交点、2个交点、3个交点时n 的值，然后结合函数图象可确定出n 的取值范围．【详解】解：（1）根据题意，一次函数5y ax =-的相关函数为5,(0)5,(0)ax x y ax x -≥⎧=⎨-+<⎩， ∴把点()5,10A -代入5y ax =-+，则(5)510a -⨯-+=，∴1a =；（2）根据题意，二次函数2142y x x =-+-的相关函数为2214,(0)214,(0)2x x x y x x x ⎧-+-≥⎪⎪=⎨⎪-+<⎪⎩， ①当m ＜0时，将B （m ，32）代入y=x 2-4x+12得m 2-4m+1322=， 解得：m=2-当m≥0时，将B （m ，32）代入y=-x 2+4x-12得：-m 2+4m-12=32， 解得：m=2综上所述：m=2m=2m=2②当-3≤x ＜0时，y=x 2-4x+12，抛物线的对称轴为x=2，此时y 随x 的增大而减小， ∴当3x =-时，有最大值，即2143(3)4(3)22y =--⨯-+=， ∴此时y 的最大值为432． 当0≤x≤3时，函数y=-x 2+4x 12-，抛物线的对称轴为x=2， 当x=0有最小值，最小值为12-，当x=2时，有最大值，最大值y=72．综上所述，当-3≤x≤3时，函数y=-x2+4x12-的相关函数的最大值为432，最小值为12-；（3）如图1所示：线段MN与二次函数y=-x2+4x+n的相关函数的图象恰有1个公共点．∴当x=2时，y=1，即-4+8+n=1，解得n=-3．如图2所示：线段MN与二次函数y=-x2+4x+n的相关函数的图象恰有3个公共点．∵抛物线y=x2-4x-n与y轴交点纵坐标为1，∴-n=1，解得：n=-1．∴当-3＜n≤-1时，线段MN与二次函数y=-x2+4x+n的相关函数的图象恰有2个公共点．如图3所示：线段MN与二次函数y=-x2+4x+n的相关函数的图象恰有3个公共点．∵抛物线y=-x2+4x+n经过点（0，1），∴n=1．如图4所示：线段MN与二次函数y=-x2+4x+n的相关函数的图象恰有2个公共点．∵抛物线y=x 2-4x-n 经过点M （12-，1）， ∴14+2-n=1，解得：n=54． ∴1＜n≤54时，线段MN 与二次函数y=-x 2+4x+n 的相关函数的图象恰有2个公共点． 综上所述，n 的取值范围是-3＜n≤-1或1＜n≤54． 【点睛】本题主要考查的是二次函数的综合应用，解答本题主要应用了二次函数的图象和性质、函数图象上点的坐标与函数解析式的关系，求得二次函数y=-x 2+4x+n 的相关函数与线段MN 恰好有1个交点、2个交点、3个交点时n 的值是解题的关键．10．(1)m=()()21200304603040t t t t +≤≤⎧⎪⎨+<≤⎪⎩, (2) t=40时w 最大=13200，(3)a 的最大值是85=2a ． 【解析】【分析】(1)由图2知m 与t 是一次函数关系，设0≤t≤30时的解析式为m=k 1t+b 1，由图形的点（0,120），（30,180）在函数图像上代入解析式即可,设3040t <≤时的解析式为m=k 2t+b 2，由图形的点（40,220），（30,180）在函数图像上 代入解析式即可，(2)由商品没有成本价，为此只要商品的销售额最大，利润就最大,设y 1的总价为w 1，y 2的总价为w 2，总价=销售单价×销售量m 即可列出, w 1=2260720022103600t t t t ⎧-++⎨-++⎩与w 2=222036003801200t t t ⎧-++⎪⎨⎪+⎩两种总销售w=w 1+w 2，把w 函数配方讨论当030t ≤≤，第一段w 最大与3040t <≤，在第二段，w 最大经比较即可(3)根据题意决定每销售1千克产品就捐赠a 元给“环保公益项目”，则捐赠额a(4t+60)后10天每日销售额Q=w-am=-2t 2+(290-4a)t+4800-60a ，Q≥3600,构造抛物线Q 在Q=3600直。
上海西南模范中学中考物理模拟试题_图文
上海西南模范中学中考物理模拟试题_图文一、选择题1．同学们梳理了教材中与压强知识相关的实验，如图所示，其中分析正确的是（）A．甲图所示，用一个装水的瓶子和海绵无法探究压力作用效果和压力大小的关系B．乙图所示，小孩通过沼泽地时垫木板可以减小对地面的压力，从而减小压强C．丙图所示，拦河大坝做成上窄下宽是因为液体压强随深度的增加而增大D．丁图所示，“瓶吞鸡蛋”实验可以说明大气压的存在，若瓶子侧放则无法完成实验2．下列自然现象中涉及到的物态变化，需要吸热的是（）A．暖春冰雪消融B．盛夏草上露珠C．凉秋雾锁江南D．寒冬北国飞雪3．如图所示，叠放在一起的物体A和B，在大小为F的恒力作用下沿水平面做匀速直线运动，则下列结论中正确的是A．甲、乙两图中A物体所受的摩擦力大小均为FB．甲、乙两图中B物体受到地面对它的摩擦力均为FC．甲图中物体A受到的摩擦力为0，物体B受到地面对它的摩擦力为FD．乙图中物体A受到的摩擦力为F，物体B受到地面对它的摩擦力为F4．关于压强，下列说法正确的是（）A．帕斯卡裂桶实验说明了液体压强与液体的重力有关B．自制气压计是利用了液体的热胀冷缩原理来反映大气压的变化C．嘴巴吸饮料入口是利用了气体流速越大，压强越小D．一个普通人单脚站立在地面上时，对地面的压强大约是2×104Pa5．如图所示的四个物态变化中，属于吸热的是( )A．春天，冰雪消融B．夏天，露珠晶莹C．秋天，白雾弥漫D．冬天，霜满枝头6．常泰大桥建设工程正如火如荼，大桥建成后将创下三个“世界第一”；世界上首座含一级公路、高速公路和城际铁路的“一桥三用”的过江通道；主桥将成为世界上最大跨度的公铁两用斜拉桥：两侧的两座拱桥也将成为世界上最大跨度的公铁两用钢拱桥，江面上航行的轮船上的船员看到工地现场正远离自己，所选取的参照物是（）A．自己所在的轮船B．岸边的建筑C．施工工地行驶的施工车D．工地上的吊车7．以下估测符合生活实际的是（）A．成人正常步行的速度约为5km/hB．学生课桌的高度约为1.8mC．一个中学生体重约为50ND．教室内一盏日光灯工作时的电流约为1A8．关于声现象，下列说法正确的是（）A．敲鼓时，鼓面振幅越大，音调越高B．敲鼓时，鼓面振动越快，响度越大C．敲鼓时，听到的声音由鼓槌的振动产生的D．敲鼓时，远处的人听到鼓声是由空气传播的9．一只手握住甲，乙两个核桃，逐渐增大握力，发现甲核桃碎裂时乙核桃完好，下列有关两个核桃相互挤压时说法正确的是（）A．甲对乙的作用力小于乙对甲的作用力B．两核桃相接触部位受到的压强相等C．甲对乙的作用力与乙对甲的作用力是一对平衡力D．甲对乙的作用力没有使乙核桃发生形变10．小阳在科技月制作了一个双档位电热器模型，为了分析接入电路的电阻对电热器的电功率的影响，他将各电表接入电路中，电路如图所示，电源两端电压不变，R1=30Ω。
上海西南模范中学中考化学模拟试题_图文
上海西南模范中学中考化学模拟试题_图文一、选择题1．可燃物R是C、H2、CH4、CO或CH4O中的一种。
将一定量的R和氧气置于一个密闭的容器中引燃，测得反应前后各物质的质量如下表：物质R氧气二氧化碳水一氧化碳反应前质量/g m1m2000反应后质量/g00m3m4m5下列叙述正确的是（）①m1=1/9m4时，R是H2②m1+m2=m3时，R是C或CO③ m3:m4=11:9时，R是CH4或CH4O④8m3/11+8m4/9+4m5/7≥m2A．①②③B．①③④C．②③④D．①②③④2．有一包固体粉末，可能含碳、铝、铜、氧化铝、氧化铜中的一种或几种。
为探究该固体粉末的组成，某化学兴趣小组进行了如下图所示实验。
下列结论正确的个数是①固体B中的物质为碳②蓝色溶液乙为硝酸铜溶液③原固体样品中一定含有的物质是碳、铝、铜④蓝色溶液丙中一定含有的溶质是硝酸铝、硝酸铜、硝酸A．1个B．2个C．3个D．4个3．金属钠非常活泼，常温下在空气中易被氧化，也易与水反应。
现将5.4g部分氧化的金属钠样品放入150g 16%的硫酸铜溶液中，充分反应后过滤，得到9.8g蓝色滤渣。
(已知样品成分仅为Na 和Na 2O ，相关反应①222Na 2H O 2NaOH H +=+↑ ②22Na O H O 2NaOH +=)，下列计算错误的是( ) A ．最终所得溶液中存在两种溶质 B ．最终所得溶液的质量为145.5g C ．原混合物中钠元素质量为4.6gD ．原混合物中钠和氧化钠的质量比为46: 314．如图所示装置进行实验（图中铁架台等仪器均已略去）。
在Ⅰ中加入试剂后，塞紧橡皮塞，立即打开止水夹，Ⅱ中有气泡冒出；一段时间后关闭止水夹，Ⅱ中液面上升，溶液由无色变为浑浊。
符合以上实验现象的Ⅰ和Ⅱ中应加入的试剂是（ ）ABCDⅠ CaCO 3、稀HCl Na 2CO 3、稀H 2SO 4 Zn 、稀H 2SO 4 Cu 、稀H 2SO 4 ⅡKNO 3NaClBaCl 2Ba(OH)2A ．AB ．BC ．CD ．D5．下列图像不能正确反映其对应变化关系的是A B C DA ．用等质量、等浓度的过氧化氢溶液在有无催化剂条件下制氧气B ．一定质量的红磷在密闭容器中燃烧C ．向等质量、等浓度的稀硫酸中分别逐渐加入锌粉和铁粉D ．向一定质量的氯化铜和稀盐酸的混合溶液中逐滴加入氢氧化钠溶液6．某气体可能含有H 2、CO 2、CO 、HCl 中的一种或几种，把该气体依次通过澄清石灰水、饱和碳酸氢钠溶液、浓硫酸、灼热的氧化铜、无水硫酸铜、澄清石灰水，观察到的现象是：前面的一瓶澄清石灰水无明显变化，灼热的氧化铜变红色，无水硫酸铜变蓝（无水硫酸铜遇水变蓝），后面的一瓶澄清石灰水变浑浊，下列关于该气体说法不正确的是（）A．一定含有H2 B．一定含有COC．可能含有HCl D．可能含有CO27．下列各组物质在溶液中能大量共存，且溶液呈无色的是（）A．Na2CO3、NH4NO3、Ca（OH）2B．Fe2（SO4）3、Na2SO4、Mg（NO3）2C．AlCl3、Ba（NO3）2、CaCl2D．Na2CO3、AgNO3、BaCl28．将铝和镁组成的混合物 10g 加入到 200g 稀盐酸中恰好完全反应后得到溶液 209g，再向溶液中加入足量的氢氧化钠溶液，最终生成沉淀的质量为（）A．12g B．14.25g C．17.25g D．27g9．不能正确反映对应变化关系的图像是（）A．在一定量的CuSO4溶液中逐滴加入NaOH溶液B．等质量的Zn和Mg分别与足量等体积等质量分数的稀硫酸反应C．向NaOH溶液中逐滴加入稀盐酸D．等质量CaCO3分别与足量等体积等质量分数的稀盐酸反应10．逻辑推理是化学学习中常用的思维方法。
上海市2017-2018学年西南模范初三上学期英语第一次月考(有答案)
西南模范2017学年第一学期初三英语阶段评估一月考Quiz III.Choose the best answer:26.Which of the following words matches the sound/keis/?A.kissB.cakeC.caveD.case27.Which of the following underlined parts is different in pronunciation from others?A.He washed his hands.B.They stopped us from coming in.C.I walked home last night.D.Louise opened a bottle of wine.28.Vivian and her friends will go abroad for a trip______July,2019.A.toB.onC.inD.at29.There_____a lot of small flats,but now most of us live in bigger ones.ed to beed to haveC.was used to beD.is used to doing30---How long has the shop_______?---For ten years.A.been openB.openedC.been openedD.opening31.With the help of the SMS service,it is______to send a text than a regular letter.A.much more quickly.B.quicklierC.much quickerD.quick32._____nice news report about F1race today it isA.What aB.WhatC.How aD.How33.The problem is______he will go for a walk with tonight.A.ifB.whoC.whenD.what34.The music from the next door sounded______.It almost drove me mad.A.beautifulB.sweetC.awfulD.healthy35.Ben______lift the heavy box by himself,so he asked his father for help.A.mustn'tB.needn'tC.couldn'tD.shouldn't36.The pizza was so big.We only had one-third of it and left_____for tomorrowA.otherB.the othersC.restD.the rest37.Y ou won't calculate faster than computers______you have a really amazing brain.A.ifB.unlessC.whenD.but38.The price of my dress isn't as_____as_____of her dress.A.expensive,/B.expensive,thatC.high,/D.high,that39.Jack has read quite______science books,but I'm sorry to say he has learnt______from them.A.few,a littleB.a few,littleC.few,littleD.a few,a little40.The number of tall buildings______greatly in Tianjin in the last few years.A.is increasingB.has increasedC.are increasedD.have increased41.It's too cold today.Would you mind______the window for me?A.closeB.closesC.closingD.to close42.When the632-meter Shanghai Tower______,it will be the second tallest building in the world.A.finishesB.finishedC.will finishD.is finished43.He has seen the film_______,so he won't go with us for the film.A.sometimesB.some timesC.some timeD.sometime44.Did you ask the teacher______day before?A.What was happened to herB.What she had happenedC.What she happenedD.What had happened to her45.A:I am afraid I can't finish my report on time.it's so difficult.第 1 页 / 共 7 页B:______.A.Sorry!I don't knowB.That really sounds good!C.Take it easy.Maybe I can helpD.Thank you for telling me!plete the following passage with the words or phrases in the box.Each can only beused once.A.washedB.thinkspletelyD.aloneE.How aboutA man goes into a pet shop and tells the owner that he wants to buy a pet that can do everything. The shop owner suggests a faithful dog.The man replies,"Come on,a dog?""The owner asks, "__46__a cat?"The man replies,"No way!A cat certainly can't do everything.I want a pet that cando everything!"The shop owner__47__for a minute,then says,"I've got it a centipede!(蜈蚣)”The man says,“A centipede?I can't imagine a centipede doing everything,but okay...I'll try a centipede,He gets the centipede home and says to the centipede,"Clean the kitchen,"Thirty minutes later,he walks into the kitchen and...it's spotlessly clean!All the dishes and bowls have been__48__, dried,and put away;the tables cleaned;the appliances sparkling;the floor waxed.He is__49__ amazed.He says to the centipede,"go clean the living room."A.furnitureB.what's going onC.experienceD.putting onE.everTwenty minutes later,he walks into the living room.The carpet has been vacuumed;the50A cleaned and dusted;the pillows on the sofa plumped;Plants watered.The man thinks to himself,"This is the most amazing thing I've__51__seen.This really is a pet that can doeverything!"Next he says to the centipede,"Run down to the comer and get me a newspaper.The centipede walks out the door.10minutes later..no centipede.20minutes later..no centipede.30 minutes later.no centipede.By this point the man is wondering__52__.So he goes to the front door, opens it..and there's the centipede sitting right outside.The man says,"Hey!!I sent you down tothe comer store45minutes ago to get me a newspaper.What's the matter?!"The centipede says,"I'm going!I'm going!I'm just__53__my shoes!"plete the sentences with the given words in their proper forms.54.Is the new building about the same_________as the TV tower?(high)55.On the__________day of this year,I wrote to Dad to tell him I love him.(four)56.Children should learn to look after__________instead of depending on their parents.(they)57.I think Tom should___________to the policeman for his rude behaviour.(apology)58.The speech__________talks about how to have a healthy die.(main)59.Keeping pet dogs is a good idea,and we can learn about__________from it.(responsible)60.The street artist__________in making the audience glad because of his performance.(success)61.Paper cutting is a___________skill with a history of thousands of years.(tradition)V.Rewrite the following sentences as required.62.He had to confirm his plane ticket in two days in advance.(改为否定句)He__________________to confirm his plane ticket in two days in advance.63.The magazine beside the TV is about how to protect the environment..(对划线部分提问)________________is about how to protect the environment?64.Peter would rather watch a competition than take part in one.(保持原句意思)Peter prefers________a competition_______taking part in one.65.We're not able to give up the life of the poor girl for the time being.(保持句意基本不变)We're not able to give up the life of the poor girl_______________.66.Jane wrote novels about nineteenth-century France a couple of years ago.(改为被动语态)第 2 页 / 共 7 页Novels about nineteenth-century France_______________a couple of years ago.67.My brother asked,"Has Lin Dan won the game?"(合并成宾语从句)My brother asked_______Lin Dan_______won the game.68.quickly,say,four seasons,in,that,can,changes,the weather,you,people,one day,so, experience(连词成句)_____________________________________________________________________.Part3Reading and Writing(第三部分读写）VI.Reading comprehension(阅读理解)A.Choose the best answer(A1)Daniel Boone was born in the United States in1734.He didn’t go to school and couldn’t read, although he learned all about the forests,streams and hunting.He could move silently like an Indian leaving no marks.He loved to live alone in the woods where nothing frightened him.When he grew up,he married and tried to settle down on a farm.A year later,however,he wasn’t satisfied and decided to go into the unknown western lands,crossing the Appalachian Mountains.When he returned after two years,he became famous for his long journey.He brought valuable animal skins and told stories about the Indians.After this,he chose to keep travelling to unknown places.Once he lost to the Indians in battleand was taken away.The Indians liked him and became his friends.Daniel Boone died at the age of86.He is remembered as an explorer and a pioneer who livedan exciting life in the early years of American nation.69.Daniel Boone’s early life was mainly spent in_________.A.learning about natureB.hunting with his friendsC.learning useful skills from the IndiansD.studying at home instead of going to school70.When he got married,Daniel Boone first planned to_________.A.set up a large farmB.go on a journey with his wifeC.find food,new land for his farmD.live a peaceful life with his family71.Why did the Indians want to make friends with him?A.Because they wanted to learn from him.B.Because he wanted to make peace with them.C.Because they wanted to make friends with white people.D.No reason is told in this article.(A2)Perhaps the most famous theory,the study of body movement,was suggested by Professor Ray Birdwhistell.He believes that physical appearance is often culturally(文化的)programmed.In other words,we learn our looks—we are not born with them.A baby has generally unformed face features(特征).A baby,according to Bird whistle,learns where to set the eyebrows(眉毛)by looking at those around—family and friends.This helps explain why the people of some areas ofthe United States look so much alike,New Englanders or Southerners have certain common face features that cannot be explained by genetics(遗传学).The exact shape of the mouth is not set at birth,it is learned after.In fact,the final mouth shape is not formed until well after new teeth areset.For many,this can be well into grown-ups.A husband and wife together for a long time often第 3 页 / 共 7 页come to look somewhat alike.We learn our looks from those around us.This is perhaps why in a single country there are areas where people smile more than those in other areas.In the United States, for example,the South is the part of the country where the people smile most frequently.In New England they smile less,and in the western part of New Y ork State still less.Many Southerners find cities such as New Y ork cold and unfriendly,partly because people on Madison Avenue smile less than people on Peachtree.Street in Atlanta,Georgi A.People in largely populated areas also smileand greet each other in public less than do people in small towns.72.Ray Birdwhistell whistle believes physical appearance_________.A.has little to do with cultureB.has much to do with cultureC.is ever changingD.is different from place to place73.According to the passage,the final mouth shape is formed_________.A.before birthB.as soon as one's teeth are newly setC.sometime after new teeth are setD.around15years old74.This passage might have been taken out of a book dealing with_________.A.physicsB.chemistryC.biologyD.body movementB.Choose the words or expressions and complete the passageAs I drove my blue Buick into the garage,I saw that a yellow Oldsmobile was parked too close tomy space.I had to drive back and forth to get my car into the___75___space.That left hardly enough room to open the door.Then one day I arrived home first,and just,as I turned off the engine, the yellow Oldsmobile entered its space—too close to my car as usual.At last I had a chance to meet the driver.My patience had___76___and I shouted at her,“Can’t you see you’re not leavingme enough space.Park father over.”Banging(猛推)open her door into___77___,the driver shouted back:“Make me!”With this she stepped out of the garage.Still,each time she got home first,she parked too close to my side.Then one day,I thought,“What can I do?”I soon found an answer.The next day the woman discovered a note on her windshield(挡风玻璃).Dear Y ellow Oldsmobile,..I’m sorry mistress(女主人)shouted at yours the other day.She’s been sorry about it.I know it because she doesn’t sing anymore while___78___.It wasn’t like her to scream like that.Fact is, she’d just got bad news and was taking it out on you two.I hope you and your mistress will forgive her.Your neighbor,Blue BuickWhen I went to the garage the next morning,the Oldsmobile was gone,but there was a note on my windshield:Dear Blue Buick,My mistress is sorry,too.She parked so___79___because she just learned to drive.W e will park much farther over after this.I’m glad we can be friends now.Your neighbor,Yellow OldsmobileAfter that,whenever Blue Buick___80___Yellow Oldsmobile on the road,their drivers waved cheerfully and smiled.plete B.close C.narrow D.fixed76.A.run into B.run about C.run out D.runoff第 4 页 / 共 7 页77.A.mine B.hers C.itself D.ours78.A.working B.driving C.returning D.cooking79.A.badly B.well C.noisily D.early80.A.followed B.passed C.found D.greetedC.Read the passage and fill in the blanks with proper wordsTeamwork is just as important in science as it is on the playing field.Scientific investigations (调查）are c___81___about by teams of people working together.Ideas are shared,experiencesare designed,data are analyzed,and results are shared with other investigators.Group work is necessary,and more productive than working alone.Several times t___82___the year you may be asked to work with one or more of your classmates.Whatever the task your group is assigned,a few rules need to be followed to get a successful experience.What comes f___83___is to keep an open mind,because everyone’s ideas deserve consideration and each group member can make his or her own contribution.Secondly,it makes ajob easier to divide the group task among all group members.Choose a role on the team that is best suited to your particular strengths.Thirdly,always work together,take turns,and encourage each other by listening,and trusting one another.Mutual support and trust often make a great d___84___.Activities like investigations are most effective when done by small groups.Here are some suggestions for effective team performance:Make sure each group member agrees to the task givento him or her,and everyone knows e___85___when,why and what to do;take turns doingv___86___tasks during similar and repeated activities;be aware of where other group members are and what they are doing so as to ensure safety;be responsible for your own learning.When there is research to be done,divide the topic into several areas.Y ou are encouraged to keep records of the sources used each person.A format for exchanging information(e.g.photocopiesof notes,oral discussion,etc.)is also important,because a well-chosen method not only strengthens what you present but also makes yourself easily u___87___.Most important of all,it is always wiseto make decisions by compromise and agreement.After you’ve completed a task with your team,make an evaluation of the team’s effectiveness —the strengths and weaknesses,opportunities and challenges.D.Answer the questionsA young and successful man was traveling down a street,going a bit too fast in his new Jaguar.He was watching for kids running out from between parked cars.As his car passed,no children appeared.Instead,a brick smashed(猛烈撞击)into the Jaguar’s side door.He was very angry and drove the car back to the place where the brick had been thrown.The angry driver jumped out ofthe car and grabbed the nearest kid,shouting，“Who are you?What are you doing?That’s a newcar and that brick you threw is going to cost a lot of money.Why did you do that?”The young boywas apologetic.“I’m sorry.I didn’t know what else to do,”he said.“I threw the brick because noone else would stop.”With tears dripping down his face,the boy pointed to a spot just around a parked car.It’s my brother,”he said,“he fell out of his wheelchair and I can’t lift him up.”The boy asked the man,“Would you please help me get him back into his wheelchair?He’s hurt第 5 页 / 共 7 页and he’s too heavy for me.”Moved beyond words,the driver hurriedly lifted the disabled boy into the wheelchair.“Thank you and God bless you,”the grateful child told the stranger.Too shook up for words,the man simply watched the little boy push his brother down the sidewalk toward their home.It was a long and slow walk back to the Jaguar.The damage was very noticeable,but the driver never bothered to repair the dented(凹陷的)side door.He kept the dent there to remind him of this message:Don’t go through life so fast that someone has to throw a brick at you to get your attention. God whispers in our souls and speaks to our hearts.Sometimes when we don't have time to listen,he has to throw a brick at us.88.Where did the story take place?89.What caused the young man to stop his car?90.Why did the boy try hard to stop the young man’s car?91.How did the boy feel when he said,“I didn’t know what else to do.’’?92.What did the young man do to help the boy?93.How do you understand the message the young man kept the dent to remind himself of“Don’tgo through life so fast that someone has to throw a brick at you to get your attention.’’?Please explain it in your own words briefly.Writing94.Write a composition in at least60words according to the given situationSuppose your school newspaper is doing a survey on the topic“The thing I’d like to do most after the entrance examination”.Please give your reply and reasons.(假设你们校报在做一个调査，调査的主题是“中考后你最想做的一件事”，请给出你的答案，并说明理由）第 6 页 / 共 7 页26-30DDCAA31-35CABCC36-40DBDBB41-45CDBDC46.E47.B48.A49.C50.A51.E52.B53.D54.height55.fourth56.themselves57.apologize58.mainly59.responsibility 60.succeeded61.traditional62.didn’t have63.Which magazine64.watching,to65.at present66.were written67.if,had68.The weather changes so quickly that people say you can experience four seasons in one day.69.A70.D71.D72.B73.C74.D75.C76.C77.A78.B79.A80.B81.carried82.through83.first84.difference85.exactly86.various87. understood.88.In the street89.The fact that a brick smashed into his car’s side door.90.Because the boy’s brother fell out of his wheelchair and the boy can’t lift him up.91.He felt apologize.92.He hurriedly lifted the disabled boy into the wheelchair.93.There is a lot in our lives worth our care.第 7 页 / 共 7 页。
上海西南模范中学初三化学中考模拟试题(含答案)
上海西南模范中学初三化学中考模拟试题(含答案)一、选择题（培优题较难）1．将一定质量的镁、锌混合物粉末放入到一定质量的硫酸铜溶液中，待反应停止后，过滤得滤渣和滤液，再向滤渣中加入足量的稀盐酸，滤渣部分溶解且有气体生成，则下列说法正确的是（ ）A ．滤渣中一定有镁、铜B ．滤渣中一定有镁、锌、铜C ．滤液中一定有硫酸铜和硫酸锌D ．滤液中一定有硫酸镁，一定没有硫酸铜 【答案】D【解析】三种金属的活动性镁>锌>铜，镁、锌混合物粉末放入到一定质量的硫酸铜溶液，镁先和硫酸铜反应生成硫酸镁和铜，然后锌和硫酸铜生成硫酸锌和铜，所以反应后溶液中一定有硫酸镁，固体中一定有铜；再向滤渣中加入足量的稀盐酸，滤渣部分溶解且有气体生成，说明固体中有活泼金属，说明硫酸铜被完全反应，所以滤液中一定没有硫酸铜；选D点睛：金属的位置越靠前，金属的活动性越强。
位置靠前的金属能将位于其后的金属从它的盐溶液中置换出来。
2．将一定质量的碳酸钙和铜粉的混合物在空气中煅烧使其完全反应，若反应前后固体的质量保持不变，则铜和碳酸钙的质量比为（ ） A ．44：25 B ．22：5C ．4：1D ．44：32【答案】A 【解析】 【详解】根据反应前后固体的质量保持不变可知，生成二氧化碳的质量等于与铜反应的氧气的质量，设生成二氧化碳的质量为A ，参加反应的碳酸钙的质量为x ，铜的质量为y 。
32 CaCO CaO+CO 100g 44xA高温100x=44AX=100A 25A=44112Δ2Cu+O 2CuO12832y A128y=32Ay＝4A铜和碳酸钙的质量比为：4A∶25A11＝44∶25故选A。
【点睛】本题中要抓住反应前后质量不变来做，分析其原因就是碳酸钙分解产生的二氧化碳质量等于跟铜反应的氧气质量。
然后根据两个化学方程式就可以就是出铜和碳酸钙的质量比。
3．一包不纯的氯化钾粉末，所含杂质可能是氯化钠、硝酸钾、硝酸钙、氯化铜、碳酸钠中的一种或几种。
上海西南模范中学初中物理九年级全册期末测试题(有答案解析)
一、选择题1．能源、信息和材料是现代社会发展的三大支柱，下列说法正确的是（）A．太阳能、石油、风能都属于可再生能源B．我国已建成的核电站是利用核聚变来发电的C．条形码扫描器中的光敏二极管使用的材料是超导材料D．火电厂提供的电能是二次能源2．生活中能量转化的实例很多，从能量转化的角度来看，下列描述错误的是A．燃料燃烧主要是把化学能转化为内能B．摩擦起电时主要将机械能转化为电能C．手机电池充电时化学能转化为电能D．电动机带动水泵把水升到高处是把电能转化为机械能3．对下列四幅图的分析正确的是A．图中蓝牙耳机是通过超声波与手机进行信号传输的B．如图装置可用来探究电流产生的热量与通电时间的关系C．图中电路能探究电磁铁磁性强弱与电流大小关系D．图中电路可以探究导体电阻与导体材料的关系4．下列关于光的说法正确的是（）A．影子和水中倒影都是由于光的直线传播形成的B．镜面反射和漫反射都遵循光的反射定律C．实像和虚像的成像原理相同D．红外线和紫外线的性质相同5．如图所示是电机示意图，对于图示的说法，正确的是A．图中绘出的是直流电动机的示意图，线圈正转到平衡位置B．图中绘出的是直流电动机的示意图，线圈受到磁场的作用力而转动C．图中绘出的是交流发电机的示意图，此时导线切割磁感线，线圈中产生电流D．图中绘出的是交流发电机的示意图，此时导线不切割磁感线，线圈中没有电流6．小明做实验时，不小心将一条形磁铁摔成两段，小明得到的是A．一段只有N极，另一段只有S极的磁铁B．两段均无磁性的铁块C．两段各有N极和S极的磁铁D．两段磁极无法确定的磁铁7．“珍爱生命，注意安全”是同学们日常生活中必须具备的意识。
下列有关安全用电的说法，不符合要求的是（）A．发现有人触电立即切断电源B．不用湿手接触用电器C．雷雨天气尽快在大树底下避雨D．用电器达到使用寿命后及时更换8．下列四种做法，符合安全用电原则的是（）A．用湿抹布擦拭正亮着的灯泡B．雷雨天气可以站在大树下避雨C．发生触电事故，应先切断电源再救人D．多个大功率用电器同时使用一个插座9．甲、乙两只灯泡的I－U关系图象如图所示，现将甲、乙两灯串联在电路中，当甲灯两端电压为2 V时，乙灯消耗的功率是（）A．2 W B．0.8 W C．1. 2 W D．3 W10．下列家用电器中，额定功率最接近1kW的是（）A．电饼铛B．笔记本电脑C．手电筒D．客厅LED照明灯11．在物理学的发展中，许多科学家做出了杰出的贡献。
上海西南模范中学中考化学模拟试题_图文
上海西南模范中学中考化学模拟试题_图文一、选择题1．水垢主要成分是碳酸钙和氢氧化镁。
现取一定量的碳酸钙和氢氧化镁的混合物，向其中加入100g 14.6%的稀盐酸，恰好完全反应后，得到 111.4g 溶液，将溶液蒸干得到 20.6g 固体，则原混合物中碳酸钙的含量约是（）A．77.5% B．63.3% C．46.7% D．22.5%2．某固体混合物由Mg和MgO组成，取该混合物与19. 6%的稀硫酸恰好完全反应（反应后溶液中无晶体析出），所得溶液蒸发82. 2g水后得到固体的质量为24g，则原混合物中氧元素的质量分数为（）A．16%B．20%C．25%D．40%3．现有一包由3.2g铜、13g锌和2g 碳组成的粉末，放到一定量的AgNO3溶液中，完全反应后得到的固体为m种，溶液中溶质为n种．下列说法中不正确的是（）A．若m=2，则n=2或3 B．若固体中金属的质量为 48g，则m=4 C．当m=3时，溶液可能呈蓝色D．反应后固体的质量不可能超过56g4．除去下列各组物质括号内的杂质，所选用的试剂及操作方法均正确的是A．Fe2O3（Fe）——用盐酸浸泡，然后过滤、洗涤、烘干B．CO（CO2）——先通入足量的浓NaOH溶液，后通过浓硫酸C．CaO（CaCO3）——加水溶解，过滤、烘干D．NaCl（Na2CO3）——加入过量CaCl2溶液，过滤、蒸发、结晶5．固体X可能由氢氧化钠、碳酸钠、氯化钠、硝酸镁、硝酸钡、硫酸钠、硫酸铜中的一种或几种物质组成（提示：以上物质中，只有氢氧化钠和碳酸钠的水溶液显碱性）。
为确定其组成，进行如下实验：①将固体X加入水中充分溶解，得到无色溶液；②测X溶液的pH，pH= 13；③向X的溶液中加入足量的硝酸钡溶液，产生白色沉淀，过滤；④向步骤③所得沉淀中加入足量的稀盐酸，沉淀不溶解；⑤向步骤③所得的滤液中加入过量的稀硝酸，再加入硝酸银溶液，产生白色沉淀。
根据以上实验信息，关于固体X组成的判断有以下几种说法：①不能确定是否有硝酸镁；②硝酸钡、硫酸铜、碳酸钠一定不存在；③硫酸钠和氢氧化钠一定存在；④不能确定是否有氯化钠。
上海市宝山区九年级物理3月月考试卷
上海市宝山区九年级物理3月月考试卷姓名:________ 班级:________ 成绩:________一、选择题 (共30题；共147分)1. （2分）如图所示，当S闭合，滑片向右移动过程中，下列说法中正确的是（）A . V1的示数增大，V2的示数减小；B . R1、R2消耗电功率的变化量一定相等；C . V1减小的示数等于V2增大的示数；D . V1减小的示数小于 V2增大的示数；2. （2分） (2017九上·滨州期中) 如图，在探究“通过导体中的电流与电阻之间关系”的实验中，当我们将电阻由5Ω换成10Ω后，接下来的操作正确的是（）A . 将变阻器滑片P向左移动，保持电压表示数不变B . 将变阻器滑片P向右移动，保持电流表示数不变C . 将变阻器滑片P向右移动，保持电压表示数不变D . 将变阻器滑片P向左移动，保持电流表示数不变3. （2分）(2018·柳州模拟) 如图是电吹风，通过用途我们可以确定组成它的电器元件。
下列一定不是组成电吹风的电器元件是（）A . 电阻丝B . 小喇叭C . 开关D . 小电风扇4. （2分） (2017九上·新泰期中) 下列关于导体的说法中，正确的是（）A . 一根金属丝被均匀拉长后，它的电阻将变大B . 导体中没有电流通过时，导体就没有电阻C . 保险丝都是用半导体材料制成的D . 粗导线的电阻一定比细导线的电阻大5. （2分）某导体中的电流与它两端的电压关系如图所示，下列分析正确的是A . 该导体的电阻随电压的增大而增大B . 该导体的电阻随电流的增大而减小C . 当导体两端的电压为0时，电阻为0D . 当导体两端的电压为0时，电流为06. （2分）(2019·宿迁) 如图所示，电源电压6V保持不变，定值电阻R1标有“10Ω0.5A”字样：滑动变阻器R2标有“20Ω1A”字样，电流表量程为0～0.6A，电压表量程为0～3V，闭合开关S，下列做法能够保证电路安全的是（）A . 电路中电流不超过B . 两端电压不超过3VC . 滑动变阻器连入电路的阻值在范围内变化D . 电路的总功率在范围内变化7. （2分）图2是甲、乙两电阻的电流与电压关系的图像，现将甲、乙串联后接在电压为4.5V的电源两端。
上海市徐汇区上海市西南模范中学2024-2025学年九年级上学期月考数学试卷(9月份)(无答案)
2024-2025学年上海市徐汇区西南模范中学九年级（上）月考数学试卷（9月份）一、选择题【下列各题的四个选项中，有且只有一个选项是正确的】1．下列条件中，不能确定一个直角三角形的条件是（ ）A．已知两条直角边B．已知两个锐角C．已知一边和一个锐角D．已知一条直角边和斜边2．如果△ABC的三边之比是3：5：7，与它相似的△A'B'C'的最短边为6，那么△A'B'C'的其余两边长的和是（ ）A．12B．19C．21D．243．在△ABC中，∠C＝90°，设∠A，∠B，∠C所对的边分别为a，b，c，则（ ）A．c＝b sin B B．b＝c sin B C．a＝b tan B D．b＝c tan B4．下列说法中，正确的是（ ）A．有一个角相等的两个菱形必相似B．有一条边相等的两个矩形必相似C．有一个角相等的两个等腰三角形必相似D．有一条边相等的两个等腰三角形必相似5．如图，在▱ABCD中，M、N为对角线BD上的两点，且BM：MN：ND＝1：2：1，联结AM并延长交BC于点E，连接EN并延长交AD于点F，则AF：FD的值为（ ）A．7：1B．8：1C．9：1D．10：16．已知：如图，△ABC中，AD⊥BC于D，下列条件：（1）∠B+∠DAC＝90°；（2）∠B＝∠DAC；（3）；（4）AB2＝BD•BC．其中一定能够判定△ABC是直角三角形的有（ ）A．0个B．1个C．2个D．3个二、填空题（本大题共12题）7．已知，则＝ ．8．如果两个相似三角形的对应中线的比是5：2，那么它们的周长比是 ．9．在比例尺为1：25000的地图上，相距6厘米的两地A、B的实际距离为 千米．10．已知点M是线段AB的黄金分割点（AM＜BM），若AB＝4，则BM＝ ．11．在△ABC中，AB＝3，AC＝2，分别反向延长AB、AC到D、E，若AD＝2，则当AE＝ 时，BC ∥DE．12．已知在△ABC中，AB＝AC＝5，BC＝8，G是△ABC的重心，则AG＝ ．13．在以O为坐标原点的直角坐标平面内有一点A（4，3），如果AO与x轴正半轴的夹角α，那么α的余弦值是 ．14．在△ABC中，∠ACB＝90°，CD⊥AB于D．若，则∠B的余切值为 ．15．如图，在平行四边形ABCD中，E是线段AB上一点，连结AC、DE交于点F．若，则＝ ．16．如图，△ABC中，AB＝AC＝4，BC＝6，点E、F在边BC上，且∠EAF＝∠C，则BF•CE＝ ．17．如图，四边形ABDC中，AC与BD交于点O，AC＝BC，∠ACB＝90°，AD⊥BD于点D．若，则＝ ．18．阅读：对于线段MN与点O（点O与MN不在同一直线上），如果同一平面内点P满足：射线OP与线段MN交于点Q，且，那么称点P为点O关于线段MN的“准射点”．问题：如图，在矩形ABCD 中，AB＝3，AD＝4，点E在边AD上，且AE＝1，联结BE，设点F是点A关于线段BE的“准射点”，且点F在矩形ABCD内部或边上，如果点C与点F之间的距离为d，那么d的取值范围为 ．三、解答题（本大题共7题）19．计算：sin230°﹣2cos30°•tan60°•sin245°．20．计算：．21．如图，已知在Rt△ABC中，∠C＝90°，sin∠ABC＝，点D在边BC上，BD＝4，联结AD，tan∠DAC ＝．（1）求边AC的长；（2）求cot∠BAD的值．22．如图，在△ABC中，点P、D分别在边BC、AC上，PA⊥AB，垂足为点A，DP⊥BC，垂足为点P，．（1）求证：AB＝AC；（2）如果AB＝5，CD＝3，求AP的长．23．如图，点A在线段BD上，在BD的同侧作等腰Rt△ABC和等腰Rt△ADE，∠ABC＝∠AED＝90°，CD与BE、AE分别交于点P、M．求证：（1）△BAE∽△CAD；（2）2CB2＝CP•CM．24．如图，在平面直角坐标系中，点A（﹣4，0）、B（0，8），点C在第一象限，点D在线段OB上，OD ＝t，∠ADC＝90°，，CE⊥OD，垂足为E，联接AB、BC．（1）请直接写出图中与△AOD相似的三角形，直接写出线段CE、OE的长（用含t的代数式表示）；（2）当∠CBA＝∠BAO时，求t的值；（3）△ABC的面积是否为定值？若是，请求出这个定值；若不是，请说明理由．25．已知：如图，在梯形ABCD中，AD∥BC，∠BAD＝90°，AD＝2，AB＝4，BC＝5，在边BC上任取一点E，联结AE，作∠FEC＝∠AEB，∠FEC的另一边EF交射线CD于点F．（1）求cos C的值；（2）如图1，当点F在线段CD上时，若，求BE的长；（3）联结AF，当△AEF是直角三角形时，直接写出BE的长．。
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2017年3月西南模范初三测试卷I. Choose the best answer31. What did the teacher ___________ you to __________ at the meeting?A. tell…sayB. ask…speakC. tell…speakD. ask…talk32. I remember ___________ a telephone call to Miss Li last night.A. makeB. to makeC. makingD. made33. Our teacher, together with all the students, __________ morning exercise every day.A. doB. doesC. is doingD. are doing34. The workers in the city ____________ for more than sixteen hours a day in old days.A. are made to workB. are made workC. were made to workD. were made work35. This winter was not too cold. The ice in the river was too thin for us _____________.A. to skate on itB. skating on itC. to skate onD. skating on36. The number of students who ___________ the English club _____________20.A. take part in, isB. join, areC. take part in, areD. join, is37. Mike studies ___________ Mary.A. not so hardly asB. as hardly asC. as hard asD. not as hard as38. They go to see their grandparents ____________ Sunday morning.A. in everyB. everyC. on everyD. in39. We had no ___________ in finding the doctor’s address.A. problemB. troubleC. questionD. matter40. Yesterday I met Miss Li in the street. She told me that she ____________ to Japan twice.A. has beenB. wentC. had beenD. has gone41. Last Teachers’ Day, the teachers received a box ____________ card.A. was filled withB. full ofC. fill withD. fulled with42. He will take part in the beginning ceremony when the new hospital ___________ to the public.A. is openB. is openedC. will openD. will be opened43. – Do you mind my taking this seat?-- ______________.A. Yes, sit down, please.B. Yes, take it, please.C. No, of course not.D. No, you can’t take it.44. He left the meeting early because he had to __________ his son from school.A. pick upB. put upC. take upD. bring up45. Mr. Black didn’t go to work yesterday because he was ill in __________ bed.A. aB. anC. theD. /46. She has made many friends ___________ she came to our school.A. beforeB. afterC. sinceD. until47. I am ___________ your view on spending pocket money. It’s reasonable.A. in favour ofB. in charge ofC. afraid ofD. famous for48. The girl needs some help, _____________?A. does sheB. need sheC. doesn’t sheD. needn’t she49. The characters need strong personalities ____________ will come across in the picture.A. whoB. whichC. whenD. where50. Steam ___________ from the basin after heating the water.A. was seen riseB. was seen to raiseC. was seen raisingD. was seen risingII. Complete the following passage with words or phrases in the box. Each word can only be usedNow satellites are helping to forecast (预报) the weather. They are ______51_______, and they can reach any part of the world. The satellites ______52______ of the atmosphere (大气), because this is where the weather ______53_______. They send these pictures to the weather stations. So meteorologists (气象学家) can see the weather of any part of the world. From the pictures, the scientists can often say _______54______.Today, nearly five hundred weather stations in sixty countries receive satellite pictures. When they receive new pictures, the meteorologists compare them with ______55______. Perhaps they may find that the clouds have changed ______56______. This may mean that the weather on the ground may soon change, too. In their next weather forecast, the meteorologists can say this.So the weather satellites are _____57______ to the meteorologists. Before satellites were invented, the scientists could forecast the weather for about 24 or 48 hours. Now they can make good forecasts for three or five days. Soon, perhaps, they may ______58______ forecast the weather for a week or more ahead (提前).III. Complete the sentences with the given words in their proper forms.59. It’s amazing to see the _____________ areas in France. (scene)60. Do you know the _____________ “Practice makes perfect”? (say)61. He’s old-fashioned and never ___________ his style. (vary)62. Tom and Tim are twins, but they have different _______________. (person)63. He was one of the ____________ artists of his time. (lead)64. We can use sound effects of add ____________. (exciting)65. For _____________, some comic strips have no frame borders. (vary)66. The young man was lucky enough to be still ____________ after the accident. (living)IV. Rewrite the sentences as required67. If she doesn’t come on time, we’ll go without her. (保持原意)We’ll go without her _____________ she _____________ on time.68. The boy was too frightened to say a word. (保持原意)The boy was __________ frightened that he __________ say a word.69. The coat cost Mary nearly a month salary, ___________ ___________? (反义疑问句)70. He was so fat that he couldn’t get through the door. (保持原意)He was not _________ ___________ to get through the door.71. Did the policemen catch the robber? (改被动语态)____________ the robber ____________ by the policemen?72. Noise pollution makes people talk more loudly than before. (保持原意)People have __________ talk more loudly than before ___________ of noise pollution.73. “Has Bob been to London?” Tom asked. (改为宾语从句)Tom asked ___________ Bob ___________ been to London.C. Read the passage and fill in the blanks with proper words.Do you love holidays, but hate the increase in weight that follows? You are not alone. Holidays are happy days with p_____86______ and delicious foods. But many people are worried about the weight that comes with these delicious foods.With proper planning, it is possible to c______87_____ your weight. The idea is to enjoy the holidays but not to eat too much. You don’t have to turn away from the foods that you enjoy. The following advice may be of some help to you.Do not m______88_____ meals. Before you leave home for a party, have a small, low-fat meal or fast food. This may help to keep you from getting too excited before the wonderful foods. Begin with clear soup and fruit or vegetables. A large glass of water before you eat may help you feel full. Use a small plate; a large plate may make you eat m______89______ than enough. Better not have high-fat foods. Choose lean(瘦的) meats. Fill your plate with salad and green vegetables.Try mints (薄荷) and fruits i______90____ you have a sweet tooth. They do not have fat l_____91_____ cream and chocolate.Don’t let exercise take a b______92______ during the holidays. A 20-minute walk after a meal can help you burn off excess calories. (多余的热量)D. Answer the questions (根据短文内容回答下列问题）No matter what happens, I 'll always be there for youIn 1989 an 8.2 earthquake almost flattened America, killing over 30,000 people in less than four minutes. In the midst of utter devastation and chaos, a father left his wife safely at home and rushed to the school where his son was supposed to be, only to discover that the building was as flat as a pancake.After the unforgettably initial shock, he remembered the promise he had made to his son: "No matter what, I'll always be there for you!" And tears began to fill his eyes. As he looked at the pile of ruins that once was the school, it looked hopeless, but he kept remembering his commitment to his son.He began to direct his attention towards where he walked his son to class at school each morning. Remembering his son's classroom would be in the back right corner of the building, he rushed there and started digging through the ruins.As he was digging, other helpless parents arrived, clutching their hearts, saying: "My son!""My daughter!" Other well-meaning parents tried to pull him off what was left of the school, saying: "It's too late! They're all dead! You can't help! Go home! Come on, face reality, there's nothing you can do!"To each parent he responded with one line: "Are you going to help me now?" And then he continued to dig for his son, stone by stone. The fire chief showed up and tried to pull him off the school's ruins saying, "Fires are breaking out, explosions are happening everywhere. You're in danger. We'll take care of it. Go home." To which this loving, caring American father asked, "Are you going to help me now?"The police came and said, "You're angry, anxious and it's over. You're endangering others. Go home. We'll handle it!" To which he replied, "Are you going to help me now?" No one helped. Courageously he went on alone because he needed to know for himself: "Is my boy alive or is he dead?" He dug for eight hours...12 hours...24 hours...36 hours...then, in the 38th hour, he pulled back a large stone and heard his son's voice. He screamed his son's name, "ARMAND!" He heard back, "Dad!?! It's me, Dad! I told the other kids not to worry. I told them that if you were alive, you'd save me and when you saved me, they'd be saved. You promised, No matter what happens, you'll always be there for you! You did it, Dad!""What's going on in there? How is it?" the father asked."There are 14 of us left out of 33, Dad. We're scared, hungry, thirsty and thankful you're here. When the building collapsed, it made a triangle, and it saved us.""Come out, boy!""No, Dad! Let the other kids out first, cause I know you'll get me! No matter what happens, I know you'll always be there for me!"93.No one knew what would happen,did they ?_______________________________________________94.How many people lost their lives in the Earthquake in less than four minutes?________________________________________________95.Why was the father so insistent that he kept looking for his son ?_______________________________________________96.All of the parents were looking for their children,weren’t they ?_________________________________________________97.What do you think of the story ?__________________________________________________98.How do you feel about the story ?_________________________________________________首字母附加篇The world p_______is growing very fast. In the last 40 years ,it has doubled . By the year 2200, it will be about 10 billion. Our cities will be much bigger. There will be more factories and more roads. We will need more water and other natural r_______. Therefore, we will have serious problems in the future, so we must change the way we use e_______and natural resources now.Every day we throw away millions of tons of rubbish. Half of this is paper that we can use again. An a_______family in Europe or America throws away more than one ton of rubbish each year, but we can r______much of it. If we recycle things, we can save money,energy and resources.A lot of rubbish, however,cannot be recycled. P________and chemicals will not disappear for hundreds of years. They pollute the air, the land and the water. Pollution will be an even bigger problem in the future. Therefore, we must stop using m_______like plastics and chemicals. Many natural resources cannot be r_______. Coal and minerals, for example, will be used up some day. Other resources take a long time to grow, such as trees, or they may not always be a______, such as water. We must learn to use less energy and fewer resources. We also have to find other w_______to make energy . We can find ways to use the sun, the wind and the sea.KeysI. A C B C C D C B B C B B C A D C A C B DII. C G I F E A B HIII. scenic saying varies personalities leading excitement variety aliveIV. unless comes so couldn’t didn’t it thin enough was caught to because if hadC篇pleasant control miss more if like breakD篇93.No,they didn’t94.Over 30000 people95.Because he made the promise to his son that no matter what ,he would always be there for him.96.No ,they weren’t97.it’s moving98.He is a brave boy附加篇：Population resources energy average reducePlastics materials renewable available ways。