2008年辽宁省大连市中考数学试题及答案(word版)
2008年辽宁省中考数学试题及答案
2008年辽宁省十二市中考数学试卷*考试时间120分钟 试卷满分150分一、选择题(每小题3分,共24分)1.截止2008年6月7日12时,全国各地支援四川地震灾区的临时安置房已经安装了40600套.这个数用科学记数法表示为( ) A .50.40610⨯套B .44.0610⨯套C .340.610⨯套D .240610⨯套2.如图1,直线12l l ∥,l 分别与12l l ,相交,如果2120∠=,那么1∠的度数是( )A .30 B .45 C .60 D .753.下列事件中是必然事件的是( ) A .阴天一定下雨B .随机掷一枚质地均匀的硬币,正面朝上C .男生的身高一定比女生高D .将油滴在水中,油会浮在水面上4.图2是由几个相同的小正方体搭成的一个几何体,它的俯视图是( )5.下列命题中正确的是( )A .两条对角线互相平分的四边形是平行四边形B .两条对角线相等的四边形是矩形C .两条对角线互相垂直的四边形是菱形D .两条对角线互相垂直且平分的四边形是正方形 6.若反比例函数(0)ky k x=≠的图象经过点(21)-,,则这个函数的图象一定经过点( ) A .122⎛⎫- ⎪⎝⎭,B .(12),C .112⎛⎫- ⎪⎝⎭,D .(12)-, 7.不等式组2133x x +⎧⎨>-⎩≤的解集在数轴上表示正确的是( )8.图3是对称中心为点O 的正八边形.如果用一个含45角的直角三角板的角,借助点O (使角的顶点落在点O 处)把这个正八边形的面积n 等分. 那么n 的所有可能的值有( )A .2个B .3个C .4个D .5个二、填空题(每小题3分,共24分)A .B .C .D .图2A .B .C .D .l l 1 l 212 图1图39.分解因式:34x y xy -= .10.体育老师对甲、乙两名同学分别进行了8次跳高测试,经计算这两名同学成绩的平均数相同,甲同学的方差是2 6.4S =甲,乙同学的方差是28.2S =乙,那么这两名同学跳高成绩比较稳定的是 同学. 11.一元二次方程2210x x -+=的解是 .12.如图4,D E ,分别是ABC △的边A B A C ,上的点,DE BC ∥,2ADDB=,则:A D E A B CS S =△△.13.如图5,假设可以在图中每个小正方形内任意取点(每个小正方形除颜色外完全相同),那么这个点取在阴影部分的概率是 .14.一个圆锥底面周长为4πcm ,母线长为5cm ,则这个圆锥的侧面积是 .15.如图6,观察下列图案,它们都是由边长为1cm 的小正方形按一定规律拼接而成的,依此规律,则第16个图案中的小正方形有 个.图616.如图7,直线3y x =+x 轴、y 轴分别相交于A B , 两点,圆心P 的坐标为(10),,P 与y 轴相切于点O .若将P沿x 轴向左移动,当P 与该直线相交时,横坐标为整数的点P有 个.三、(每小题8分,共16分)17.先化简,再求值:23111a a a a a a-⎛⎫- ⎪-+⎝⎭,其中2a =.图5图案1图案2图案3 图案4……AE CD B图418.如图8所示,在网格中建立了平面直角坐标系,每个小正方形的边长均为1个单位长度,将四边形ABCD 绕坐标原点O 按顺时针方向旋转180后得到四边形1111A B C D .(1)直接写出1D 点的坐标;(2)将四边形1111A B C D 平移,得到四边形2222A B C D ,若2(45)D ,,画出平移后的图形.(友情提示:画图时请不要涂错阴影的位置哦!)四、(每小题10分,共20分)19.如图9,有四张背面相同的纸牌A B C D ,,,,其正面分别画有四个不同的图形,小明将这四张纸牌背面朝上洗匀后随机摸出一张,放回后洗匀再随机摸出一张.(1)用树状图(或列表法)表示两次摸牌所有可能出现的结果(纸牌用A B C D ,,,表示); (2)求两次摸牌的牌面图形既是中心对称图形又是轴对称图形的概率.20.如图10,AB 为O 的直径,D 为弦BE 的中点,连接OD 并延长交O 于点F ,与过B 点的切线相交于点C .若点E 为AF 的中点,连接AE . 求证:ABE OCB △≌△.图8图9图10ODB CF EA五、(每小题10分,共20分)21.某中学开展以“我最喜欢的职业”为主题的调查活动.通过对学生的随机抽样调查得到一组数据,下面两图(如图11、图12)是根据这组数据绘制的两幅不完整的统计图.请你根据图中所提供的信息解答下列问题:(1)求在这次活动中一共调查了多少名学生?(2)在扇形统计图中,求“教师”所在扇形的圆心角的度数. (3)补全两幅统计图.22.在“汶川地震”捐款活动中,某同学对甲、乙两班捐款情况进行了统计:甲班捐款人数比乙班捐款人数多3人,甲班共捐款2400元,乙班共捐款1800元,乙班平均每人捐款的钱数是甲班平均每人捐款钱数的45倍.求甲、乙两班各有多少人捐款? 六、(每小题10分,共20分)23.如图13,某数学兴趣小组在活动课上测量学校旗杆高度.已知小明的眼睛与地面的距离()AB 是1.7m ,看旗杆顶部M 的仰角为45;小红的眼睛与地面的距离()CD 是 1.5m ,看旗杆顶部M 的仰角为30.两人相距28米且位于旗杆两侧(点B N D ,,在同一条直线上).请求出旗杆MN 的高度.1.41.7,结果保留整数)其它 教师 医生 公务员 军人10% 20% 15% 图11 图12MN BA DC30° 45°图1324.2008年6月1日起,我国实施“限塑令”,开始有偿使用环保购物袋.为了满足市场需求,某厂家生产A B ,两种款式的布质环保购物袋,每天共生产4500个,两种购物袋的成本和售价如下表,设每天生产A 种购物袋x 个,每天共获利y 元.(1)求出y 与x (2)如果该厂每天最多投入成本10000元,那么每天最多获利多少元? 七、(本题12分)25.如图14,在Rt ABC △中,90A ∠=,AB AC =,BC =另有一等腰梯形DEFG (GF DE ∥)的底边DE 与BC 重合,两腰分别落在AB AC ,上,且G F ,分别是AB AC ,的中点. (1)求等腰梯形DEFG 的面积;(2)操作:固定ABC △,将等腰梯形DEFG 以每秒1个单位的速度沿BC 方向向右运动,直到点D 与点C 重合时停止.设运动时间为x 秒,运动后的等腰梯形为DEF G ''(如图15).探究1:在运动过程中,四边形BDG G '能否是菱形?若能,请求出此时x 的值;若不能,请说明理由.探究2:设在运动过程中ABC △与等腰梯形DEFG 重叠部分的面积为y ,求y 与x 的函数关系式.A F G (D )BC (E ) 图14F GA F 'G 'BDCE图15八、(本题14分)26.如图16,在平面直角坐标系中,直线y=与x轴交于点A,与y轴交于点C,抛物线2(0)3y ax x c a=-+≠经过A B C,,三点.(1)求过A B C,,三点抛物线的解析式并求出顶点F的坐标;(2)在抛物线上是否存在点P,使ABP△为直角三角形,若存在,直接写出P点坐标;若不存在,请说明理由;(3)试探究在直线AC上是否存在一点M,使得MBF△的周长最小,若存在,求出M点的坐标;若不存在,请说明理由.x2008年辽宁省十二市中考数学试卷(六三制)答案9.(2)(2)xy x x +-10.甲11.121x x ==12.4:913.72514.210cm π(丢单位扣1分) 15.13616.3三、(每小题8分,共16分)17.解法一:原式223(1)(1)11a a a a a a a +---=⨯- ················ 2分 24a =+ ································· 6分当2a =时,原式2248=⨯+= ······················· 8分解法二:原式3(1)(1)(1)(1)11a a a a a a a a a a+-+-=⨯-⨯-+ ············ 2分 24a =+ ································· 6分 当2a =时,原式2248=⨯+= ······················· 8分18.解:(1)1(31)D -, ······························ 2分 (2)2A ,222B C D ,,描对一个点给1分. ·················· 6分 画出正确图形(见图1) ·························· 8分图1四、(每小题10分,共20分) 19.(1·············· 6分(2)从表中可以得到,两次摸牌所有可能出现的结果共有16种,其中既是中心对称图形又是轴对称图形的有9种. ································ 8分 故所求概率是916. ···························· 10分 19.(1)解法二:所以可能出现的结果:(A ,A ),(A ,B ),(A ,C ),(A ,D ),(B ,A ),(B ,B ),(B ,C ),(B ,D ),(C ,A ),(C ,B ),(C ,C ),(C ,D ),(D ,A ),(D ,B ),(D ,C ),(D ,D ). ······················· 6分 (2)以下同解法1. 20.解:(1)证明:如图2. AB 是O 的直径.90E ∴∠= ···················· 1分又BC 是O 的切线,90OBC ∴∠=E OBC ∴∠=∠ ·················· 3分 OD 过圆心,BD DE =,EF FB ∴=BOC A ∴∠=∠. ····························· 6分 E 为AF 中点,EF BF AE ∴==30ABE ∴∠= ······························ 8分 90E ∠= 12AE AB OB ∴== ···························· 9分 A B C DA ABC DB A BC DC A B C DD 开始第一次牌面的字母第二次牌面的字母 图2OD BC F EAABE OCB ∴△≌△. ·························· 10分五、(每小题10分,共20分) 21.(1)被调查的学生数为4020020=%(人) ·················· 2分 (2)“教师”所在扇形的圆心角的度数为70115201010036072200⎛⎫----⨯⨯= ⎪⎝⎭%%%% ··············· 5分(3)如图3,补全图 ···························· 8分如图4,补全图 ····························· 10分22.解法一:设乙班有x 人捐款,则甲班有(3)x +人捐款. ··········· 1分 根据题意得:24004180035x x⨯=+ ····························· 5分 解这个方程得45x =. ··························· 8分 经检验45x =是所列方程的根. ······················· 9分 348x ∴+=(人)答:甲班有48人捐款,乙班有45人捐款. ················· 10分 解法二:设甲班有x 人捐款,则乙班有(3)x -人捐款. ············· 1分 根据题意得:24004180053x x ⨯=- ····························· 5分 解这个方程得48x =. ··························· 8分 经检验48x =是所列方程的根. ······················· 9分 345x ∴-=(人)答:甲班有48人捐款,乙班有45人捐款. ················· 10分 六、(每小题10分,共20分) 23.解法一:解:过点A 作AE MN ⊥于E ,过点C 作CF MN ⊥于F , ··········· 1分 则 1.7 1.50.2EF AB CD =-=-= ······················ 2分 在Rt AEM △中,90AEM ∠=,45MAE ∠=AE ME ∴= ............................... 3分 设AE ME x ==(不设参数也可) 0.2MF x ∴=+,28FC x =- (5)分其它 教师医生 公务员 军人10%20%15%图3图435%20%M在Rt MFC △中,90MFC ∠=,30MCF ∠=tan MF CF MCF ∴=∠0.2(28)3x x ∴+=-············· 7分 10.0x ∴≈ 12MN ∴≈ ································ 9分答:旗杆高约为12米. ·························· 10分 解法二:解:过点A 作AE MN ⊥于E ,过点C 作CF MN ⊥于F , ······· 1分 则 1.7 1.50.2EF AB CD =-=-= ······················ 2分 在Rt AEM △中,90AEM ∠=,45MAE ∠=AE ME ∴=设AE x =,则0.2MF x =+ ························ 3分在Rt MFC △中,90MFC ∠=,30MCF ∠=tan603(0.2)CF MF x ==+······················· 5分 BN ND BD +=0.2)28x x ∴+= ··························· 7分解得10.2x ≈12MN ∴≈ ································ 9分 答:旗杆高约为12米. ·························· 10分 (注:其他方法参照给分) 24.解:(1)根据题意得:(2.32)(3.53)(4500)0.22250y x x x =-+--=-+ ······ 2分 (2)根据题意得:23(4500)10000x x +-≤ ················· 5分 解得3500x ≥元 ······························ 6分0.20k =-<,y ∴随x 增大而减小 ····················· 8分∴当3500x =时0.2350022501550y =-⨯+= ······················· 9分答:该厂每天至多获利1550元. ······················ 10分七、(本题12分) 25.解:如图6,(1)过点G 作GM BC ⊥于M .AB AC =,90BAC ∠=,BC =G 为AB 中点GM ∴= ············ 1分又G F ,分别为AB AC ,的中点12GF BC ∴==········· 2分162DEFG S ∴==梯形 ∴等腰梯形DEFG 的面积为6. ······················· 3分(2)能为菱形 ······························· 4分如图7,由BG DG '∥,GG BC '∥∴四边形BDG G '是平行四边形 ····· 6分当122BD BG AB ===时,四边形BDG G '为菱形,此时可求得2x =∴当2x =秒时,四边形BDG G '为菱形.· 8分 (3)分两种情况:①当0x <≤方法一:GM =BDG GS'∴=∴重叠部分的面积为:6y =∴当0x <≤y 与x的函数关系式为6y = ··········· 10分方法二:当0x <≤FG x '=,DC x =,GM =∴重叠部分的面积为:))62x x y +==∴当0x <≤y 与x的函数关系式为6y = ··········· 10分②当x ≤设FC 与DG '交于点P ,则45PDC PCD ∠=∠= 90CPD ∴∠=,PC PD =AFG (D )B C (E ) 图6M F G A F 'G ' BD CE图7MF GAF 'G 'BCEQ D P作PQ DC ⊥于Q,则1)2PQ DQ QC x ===∴重叠部分的面积为:221111)))82244y x x x x =⨯==-+ ········ 12分八、(本题14分) 26.解:(1)直线y =x 轴交于点A ,与y 轴交于点C .(10)A ∴-,,(0C ·························· 1分点A C ,都在抛物线上,0a c c⎧=++⎪∴⎨⎪=⎩a c ⎧=⎪∴⎨⎪=⎩ ∴抛物线的解析式为233y x x =- ················· 3分 ∴顶点13F ⎛- ⎝⎭, ···························· 4分 (2)存在 ································· 5分1(0P ································ 7分2(2P ································ 9分 (3)存在 ································ 10分理由: 解法一:延长BC 到点B ',使B C BC '=,连接B F '交直线AC 于点M ,则点M 就是所求的点. ························· 11分 过点B '作B H AB '⊥于点H .B点在抛物线2y x x =(30)B ∴,在Rt BOC △中,tan 3OBC ∠=,30OBC ∴∠=,BC =在Rt BB H '△中,12B H BB ''==6BH H '==,3OH ∴=,(3B '∴--, ·············· 12分x设直线B F'的解析式为y kx b=+3k bk b⎧-=-+⎪∴⎨=+⎪⎩解得6kb⎧=⎪⎪⎨⎪=⎪⎩y x∴=····························13分yy x⎧=-⎪∴⎨=⎪⎩解得37xy⎧=⎪⎪⎨⎪=⎪⎩37M⎛∴⎝⎭,∴在直线AC上存在点M,使得MBF△的周长最小,此时37M⎛⎝⎭,.·14分解法二:过点F作AC的垂线交y轴于点H,则点H为点F关于直线AC的对称点.连接BH交AC于点M,则点M即为所求.·················11分过点F作FG y⊥轴于点G,则OB FG∥,BC FH∥.90BOC FGH∴∠=∠=,BCO FHG∠=∠HFG CBO∴∠=∠同方法一可求得(30)B,.在Rt BOC△中,tan OBC∠=,30OBC∴∠=,可求得GH GC==,GF∴为线段CH的垂直平分线,可证得CFH△为等边三角形,AC∴垂直平分FH.即点H为点F关于AC的对称点.0H⎛∴⎝⎭,·············12分设直线BH的解析式为y kx b=+,由题意得03k bb=+⎧⎪⎨=⎪⎩解得kb⎧=⎪⎪⎨⎪=⎪⎩xy ∴=···························· 13分y y ⎧=-⎪∴⎨⎪=⎩解得37x y ⎧=⎪⎪⎨⎪=⎪⎩377M ⎛∴- ⎝⎭, ∴在直线AC 上存在点M ,使得MBF △的周长最小,此时37M ⎛ ⎝⎭,. · 14分。
2008年大连市初中毕业升学统一考试
2008年大连市初中毕业升学统一考试本试卷1~8页,满分100分。
考试时间100分钟。
一、填空题(本题共12小题,每小题2分,共24分)1.小明乘坐游艇在海上航行。
以海岸为参照物,小明是_________的;以_________为参照物,小明是静止的。
2.原子的中心是原子核,原子核是由带_________电的质子和不带电的_________组成。
3.往暖水瓶中灌水时,可以根据发出声音的_________变化来判断暖水瓶中水的多少;听音乐时,我们能分辨出小号声和钢琴声,是因为这两种乐器发出声音的_________不同。
4.煤、石油和天然气属于_________再生能源;核电站的核反应堆中发生的是可以控制的核_________变。
5.自行车把手上刻有凹凸不平的花纹,是为了_________摩擦;自行车刹车时,是通过增大刹车皮与车圈之间的_________来增大摩擦。
6.给蓄电池充电的过程中,电能转化为蓄电池的_________能;用手机打电话时,是利用_________来传递信息的。
7.白炽灯用久了灯丝变细,灯丝电阻变_________;滑动变阻器是通过改变连入电路中的电阻丝的_________来改变电阻的。
8.看电影时,因为电影幕布发生_________反射,所以各个方向的观众都能看到画面;看话剧时,一位演员穿红色上衣,在蓝色灯光的照射下,观众看到她的上衣是_________色。
9.如图1所示,闭合开关,小磁针静止时N极指向通电螺线管的6端。
则通电螺线管的n端是_________极;在滑动变阻器的滑片向右移动过程中,通电螺线管对小磁针的磁力逐渐_________。
10.如图2所示,一束光线从空气斜射入水中。
请画出折射光线的大致方向。
11.请将图3中的各元件符号连成电路图。
要求两灯并联,开关同时控制两盏灯。
12.图4是用杠杆吊重物的示意图。
请画出拉力F1。
对支点O的力臂,并画出挂重物的细绳对杠杆的拉力的示意图。
大连市初中毕业中考数学试题无答案
总票数:21774选项 百分比 列车员态度 21.3%超载 41.96% 车厢卫生 16.91%物价太贵 19.79%FOEDCB A2008年辽宁省大连市初中毕业中考数学升学统一考试试题本试卷1~8页,共150分,考试时间120分钟。
一、选择题(本题8小题,每小题3分,共24分)说明:将下列各题唯一正确的答案代号A 、B 、C 、D 填到题后的括号内。
1.在平面直角坐标系中,点P (2,3)在 ( )A .第一象限B .第二象限C .第三象限D .第四象限 2.下列运算中,结果正确的是 ( ) A .3412a a a ⋅= B .1025a a a ÷= C .235aa a += D .43a a a -=3.2007年8月对列车服务情况进行了调查,其中不满意情况的百分比如图1,由图中的数据可知,列车服务最需要 改进的方面是 ( )A .列车员态度B .超载C . 车厢卫生D .物价太贵 4.如图,两温度计读数分别为我国某地今年2月份某天的最 低气温与最高气温,那么这天的最高气温比最低气温高( ) A .5°C B .7°C C .12°C D .-12°C5.在共有15人参加的的“我爱祖国”演讲比赛中,参赛选手要想知道自己是否能进入前8名,只需要了解自己的成绩以及全部成绩的 ( )A .中位数B .众数C .平均数D .方差 6.下列图形中,恰好能与图3拼成一个矩形的是 ( )7.若运算程序为:输出的数比该数的平方小1.则输入23 ( ) A .10 B .11 C .12 D .138.如图,梯形ABCD 中,AD ∥BC ,中位线EF 交BD 于点O , 若FO -EO = 5,则BC -AD 为( )二、填空题(本题共8小题,每小题3分,共24分) 说明:将答案直接填在题后的横线上。
9.若两圆的半径分别为5和2,圆心距为7,则这两个圆的位置关系是__________. 10.小明和小红练习射击,第一轮10枪打完后两人的成绩如图5, 一般新手的成绩不太稳定,小明和小红二人有一人是新手,估计 小明和小红两人中新手是______________.11.关于x 的某个不等式组的解集在数轴上表示为如图6,则不等式 组的解集为_________________________.12.如图,锐角三角形ABC 的边AB 和AC 上的高线CE 和BF 相交于点D . 请写出图中的一对相似三角形______________________. 13.△ABC 平移到△DEF ,若AD = 5,则CF 为_____________.阅卷人 得分阅卷人 得分OCB14.反比例函数ky x=的图象经过点(2,3),则这个反比例函数 的解析式为_______________.15.如图,画出△OAB 绕O 点按逆时针方向旋转90°时 的△OA ′B ′. 16.若12x =,12y =,则x + y 的 值为______________.三、解答题(本题共4小题,其中17、18题各9分,19题10分,20题各12分,共40分)17.化简:2231693a a a a a a-÷++++ 18.如图,一块长方形铁皮的长是宽的2倍,四个角各截去一个正方形,制成高是5cm ,容积是500cm 3的无盖长方体容器,求这块铁皮的长和宽.19.如图,PA 、PB 是⊙O 的切线,切点分别为A 、B 、C 是⊙O 上一点,若∠APB = 40°,求∠ACB 的度数. 20.某活动小组为了估计装有5个白球和若干个红球(每个球除颜色外都相同)的袋中红球接近多少个,在不将袋中球倒出来的情况下,分小组进行摸球试验,两人一组,共20组进行摸球实验.其中一位学生摸球,另一位学生记录所摸球的颜色,并将球放回袋中摇匀,每一组做400次试验,汇兑起来后,摸到红球次数为6000次. ⑴估计从袋中任意摸出一个球,恰好是红球的概率是多少? ⑵请你估计袋中红球接近多少个? 四、解答题(本题共3小题,其中21、22题各10分,23题各8分,共28分)2ax bx +的图象经过点(2,0)、(-1,6). ⑴求二次函数的解析式;⑵不用列表,在下图中画出函数图象,观察图象写出y > 0时,x 的取值范围.22.为了测得学校旗杆的高度,小明先站在地面的A 点测得旗杆最高点C 的仰角为27°(点A 距旗杆的距离大于50m),然后他向旗杆的方向向前进了50m ,此时测得点C 的仰角为40度.又已知小明的眼睛离地面1.6m ,请你画出小明测量的示意图,并帮小明计算学校旗杆的高度.(精确到0.1m).23.某仓库甲、乙、丙三辆运货车,每辆车只负责进货或出货,每小时的运输量丙车最多,乙四最少,乙车的运输量为每小时6吨,下图是从早晨上班开始库存量y (吨)与时间x (小时)的函数图象,OA 段只有甲、丙车工作,AB 段只有乙、丙车工作,BC 段只有甲、乙工作. ⑴从早晨上班开始,库存每增加2吨,需要几小时? ⑵问甲、乙、丙三辆车,谁是进货车,谁是出货车?⑶若甲、乙、丙三车一起工作,一天工作8小时,仓库的库存量有什么变化?(本题共3小题,24题 10分,25题14分,26题10分,共34分, 附加题5分,全卷累积不超过150分,建议考生最后答附加题)2y x =的顶点为P ,A 、B 是抛物线上两点,AB ∥x 轴,四边形ABCD 为矩形,CD 边经过点P ,AB = 2AD . ⑴求矩形ABCD 的面积;⑵如图24-2,若将抛物线“2y x =”,改为抛物线“2y x bx c =++”,其他条件不变,请猜想矩形ABCD图24-1的面积;⑶若将抛物线“2y x bx c =++”改为抛物线“2y ax bx c =++”,其他条件不变,请猜想矩形ABCD 的面积(用a 、b 、c 表示,并直接写出答案).附加题:若将24题中“2y x =”改为“2y ax bx c =++”,“AB = 2AD ”条件不要,其他条件不变,探索矩形ABCD 面积为常数时,矩形ABCD 需要满足什么条件?并说明理由.25.如图25-1,正方形ABCD 和正方形QMNP ,∠M =∠B ,M 是正方形于F ,QM 交AD 于E . ⑴求证:ME = MF .⑵如图25-2线段MF 的关系,并加以证明.⑶如图25-3,若将原题中的“正方形”改为“矩形”,且AB = m BC 索线段ME 与线段MF 的关系,并说明理由.⑷根据前面的探索和图25-4,你能否将本题推广到一般的平行四边形情况?若能,写出推广命题;若不能,请说明理由.26.如图,△ABC 的高AD 为3,BC 为4,直线EF ∥BC ,交线段AB 于E 于G ,以EF 为斜边作等腰直角三角形PEF (点P 与点A 在直线EF 的异侧),设EF 为x ,△PEF 与四边形BCEF 重合部分的面积为y . ⑴求线段AG (用x 表示);⑵求y 与x 的函数关系式,并求x 的取值范围.。
2008年大连市初中毕业升学统一考试
2008年大连市初中毕业升学统一考试物理本试卷1~8页。
满分100分。
考试时间100分钟。
一、填空题(本题共12小题,每小题2分。
共24分)1.小明乘坐游艇在海上航行。
以海岸为参照物,小明是_______的;以_______为参照物,小明是静止的。
2.原子的中心是原子核,原子核是由带_________电的质子和不带电的________组成。
3.往暖水瓶中灌水时,可以根据发出声音的_________变化来判断暖水瓶中水的多少;听音乐时,我们能分辨出小号声和钢琴声,是因为这两种乐器发出声音的________不同。
4.煤、石油和天然气属于__________再生能源;核电站的核反应堆中发生的是可以控制的核____________变。
5.自行车把手上刻有凹凸不平的花纹,是为了_______摩擦;自行车刹车时,是通过增大刹车皮与车圈之间的__________来增大摩擦。
6.给蓄电池充电的过程中,电能转化为蓄电池的__________能;用手机打电话时,是利用 ___________来传递信息的。
7.白炽灯用久了灯丝变细,灯丝电阻变_________;滑动变阻器是通过改变连入电路中的电阻丝的___________来改变电阻的。
8.看电影时,因为电影幕布发生_________反射,所以各个方向的观众都能看到画面;看话剧时,一位演员穿红色上衣,在蓝色灯光的照射下,观众看到她的上衣是______色。
9.如图1所示,闭合开关,小磁针静止时N极指向通电螺线管的b端。
则通电螺线管的a端是______极;在滑动变阻器的滑片向右移动过程中,通电螺线管对小磁针的磁力逐渐________。
10.如图2所示,一束光线从空气斜射入水中。
请画出折射光线的大致方向。
图2 图3 图411.请将图3中的各元件符号连成电路图。
要求两灯并联,开关同时控制两盏灯。
12.图4是用杠杆吊重物的示意图。
请画出拉力F1对支点0的力臂,并画出挂重物的细绳对杠杆的拉力的示意图。
08年
2004年大连市初中毕业升学统一考试数 学本试卷1~8页,共150分.考试时间120分钟.请考生准备好圆规、直尺、三角板、计算器等答题工具.一、选择题(本题共7小题,每小题3分,共21分)说明:将下列各题惟一正确的答案代号A 、B 、C 、D 填到题后的括号内. 1.3的相反数是( )A .33- B .3- C .33 D .32.在平面直角坐标系中,点(-1,-2)所在的象限是( ) A .第一象限 B .第二象限 C .第三象限 D .第四象限3.如图1,A 、B 、C 是⊙O 上的三点,∠BAC =30°,则∠BOC 的大小是( )图1A .60°B .45°C .30°D .15° 4.一元二次方程0422=++x x 的根的情况是( ) A .有一个实数根 B .有两个相等的实数根 C .有两个不相等的实数根 D .没有实数根5.在Rt △ABC 中,∠C =90°,a =1,c =4,则sin A 的值是( ) A .1515 B .41 C .31 D .4156.如图2,直线y =k x +b 与x 轴交于点(-4,0),则y >0时,x 的取值范围是( )图2A .x >4B .x >0C .x <-4D .x <07.将一圆形纸片对折后再对折,得到图3,然后沿着图中的虚线剪开,得到两部分,其中一部分展开后的平面图形是( )图3二、填空题(本题共7小题,每小题3分,共21分) 说明:将下列各题结果直接填在题后的横线上.8.早春二月的某一天,大连市南部地区的平均气温为-3℃,北部地区的平均气温为-6℃,则当天南部地区比北部地区的平均气温高________________℃. 9.函数1-=x y 中,自变量x 的取值范围是________________.10.关于x 的一元二次方程02=++c bx x 的两根为11=x ,22=x ,则c bx x ++2分解因式的结果为________________.11.如图4,⊙O 的半径为5cm ,圆心O 到弦AB 的距离为3cm ,则弦AB 的长为________ ________________________cm .图412.大连市内与庄河两地之间的距离是160千米.若汽车以平均每小时80千米的速度从大连市内开往庄河,则汽车距庄河的路程y (千米)与行驶的时间x (小时)之间的函数关系式为________________________.13.边长为6的正六边形外接圆的半径是________________________.14.将一个底面半径为2cm ,高为4cm 的圆柱形纸筒沿一条母线剪开,所得到的侧面展开图的面积为________________________2cm .三、解答题(本题共6小题,其中15、16题各8分,17、18、19题各10分,20题12分,共58分) 15.反比例函数xk y =的图象经过点A (2,3).(1)求这个函数的解析式;(2)请判断点B (1,6)是否在这个反比例函数的图象上,并说明理由16.如图5,某校自行车棚的人字架棚顶为等腰三角形,D 是AB 的中点,中柱CD =1米,∠A =27°,求跨度AB 的长(精确到0.01米).图517.解方程组⎩⎨⎧=-+=.,022y x x y18.某工程队承担了修建长30米地下通道的任务,由于工作需要,实际施工时每周比原计划多修1米,结果比原计划提前1周完成.求该工程队原计划每周修建多少米?19.如图6,AB 、CD 是⊙O 的直径,DF 、BE 是弦,且DF =BE . 求证:∠D =∠B .图620.未成年人思想道德建设越来越受到社会的关注.某青少年研究所随机调查了大连市内某校100名学生寒假中花零花钱的数量(钱数取整数元),以便引导学生树立正确的消费观.根据调查数据制成了频率分布表和频率分布直方图(如图7).频率分布表图7(1)补全频率分布表;(2)在频率分布直方图中,长方形ABCD的面积是________;这次调查的样本容量是________;(3)研究所认为,应对消费150元以上的学生提出勤俭节约的建议.试估计应对该校1000名学生中约多少名学生提出这项建议?四、解答题(本题共3小题,其中21题7分,22题8分,23题9分,共24分)2经过点A(1,0),与y轴交于点B.21.如图8,抛物线n=5-xxy++(1)求抛物线的解析式;(2)P是y轴正半轴上一点,且△PAB是以AB为腰的等腰三角形,试求P点坐标.图822.如图9-(1)、9-(2)、…、9-(m)是边长均大于2的三角形、四边形、…、凸n边形.分别以它们的各顶点为圆心,以1为半径画弧与两邻边相交,得到3条弧、4条弧、…、n条弧.图9-1(1)图9-(2)图9-(m)(1)图9-(1)中3条弧的弧长的和为______________,图9-(2)中4条弧的弧长的和为______________;(2)求图9-(m)中n条弧的弧长的和(用n表示).23.4×100米接力赛是学校运动会最精彩的项目之一.图10中的实线和虚线分别是初三·一班、初三·二班代表队在比赛时运动员所跑的路程y(米)与所用时间x(秒)的函数图象(假设每名运动员跑步速度不变,交接棒时间忽略不计).图10五、解答题和附加题(解答题共3小题,其中24、25题各8分,26题10分,共26分;附加题5分,但全卷累计不超过150分)24.如图11,⊙O 的直径DF 与弦AB 交于点E ,C 为⊙O 外一点,CB ⊥AB ,G 是直线CD 上一点,∠ADG =∠ABD .求证:DF DE CE AD ⋅⋅=. 说明:(1)如果你经历反复探索,没有找到解决问题的方法,请你把探索过程中的某种思路推导过程写出来(要求至少写3步).(2)在你经历说明(1)的过程之后,可以从下列①、②、③中选取一个补充或更换已知条件,完成你的证明.注意:选取①完成证明得8分;选取②完成证明得6分;选取③完成证明得4分. ①∠CDB =∠CEB ; ②AD ∥EC ;③∠DEC =∠ADE ,且∠CDE =90°.图1125.阅读材料,解答问题.材料:“小聪设计的一个电子游戏是:一电子跳蚤从1P (-3,9)开始,按点的横坐标依次增加1的规律,在抛物线2x y =上向右跳动,得到点2P 、3P 、4P 、5P 、…(如图12所示).过1P 、2P 、3P 分别作11H P 、22H P 、33H P 垂直于x 轴,垂足为1H 、2H 、3H ,则 332222113311321P H HP P H HP P H HP P P P S S S S 梯形梯形梯形--=∆1)14(211)49(212)19(21⨯+-⨯+-⨯+=1= ,即△321P P P 的面积为1.”图12问题:(1)求四边形4321P P P P 和四边形5432P P P P 的面积(要求:写出其中一个四边形面积的求解过程,另一个直接写出答案);(2)猜想四边形211++-n n n n P P P P 的面积,并说明理由(利用图13);图13(3)若将抛物线2x y =改为抛物线c bx x y ++=2,其它条件不变,猜想四边形211++-n n n n P P P P 的面积(直接写出答案).26.如图14,⊙1O 和⊙2O 内切于点P .C 是⊙1O 上任一点(与点P 不重合). 实验操作:将直角三角板的直角顶点放在点C 上,一条直角边经过点1O ,另一条直角边所在直线交⊙2O 于点A 、B ,直线P A 、PB 分别交⊙1O 于点E 、F ,连结CE (图15是实验操作备用图).探究:(1)你发现、有什么关系?用你学过的数学知识证明你的发现;(2)你发现线段CE 、PE 、BF 有怎样的比例关系?证明你的发现.图14 图15 图16附加题:如图16,若将上述问题的⊙1O 和⊙2O 由内切变为外切,其它条件不变,请你探究线段CE 、PE 、BF 有怎样的比例关系,并证明.参考答案一、选择题(本题共7小题,每小题3分,共21分)1.B ; 2.C ; 3.A ; 4.D ; 5.B ; 6.A ; 7.C二、填空题(本题共7小题,每小题3分,共21分) 8.3; 9.x ≥1; 10.(x -1)(x -2); 11.8; 12.y =-80x +160; 13.6; 14.16π.三、解答题(本题共6小题,其中15、16题各8分,17、18、19题各10分,20题12分,共58分)15.解:(1)∵ 点A (2,3)在函数xk y =的图象上, 1分∴ 23k =, 2分∴ k =6. 4分 ∴ 这个函数的解析式为xy 6=. 5分(2)把x =1代入xy 6=中,得616==y . 7分∴ 点B (1,6)在函数xy 6=的图象上. 8分16.解:∵△ACB 为等腰三角形,D 为AB 的中点, 1分 ∴ AB =2AD ,CD ⊥AB . 2分 在Rt △ADC 中,∵ CDADA =cot , 4分∴ ︒⋅⋅==27cot 1cot A CD AD , 5分∴ AD ≈1.963, 6分 ∴ AB =2AD =2×1.963≈3.93(米). 7分 答:跨度AB 的长为3.93米. 3分17.解:⎩⎨⎧=-+=②①.,022y x x y把①代入②,得 1分 022=-+x x . 4分 解得11=x ,22-=x . 6分 把11=x 代入①,得11=y ; 7分 把22-=x 代入①,得22-=y . 8分 所以原方程组的解是⎩⎨⎧==;,1111y x ⎩⎨⎧-=-=.,2222y x 10分18.解:设该工程队原计划每周修建x 米, 1分 根据题意,得130130+=-x x . 5分整理,得,0302=-+x x . 6分 解这个方程,得61-=x ,52=x . 7分 经检验,61-=x ,52=x 都是原方程的根. 8分 但时间不可能为负数,所以x =5. 9分 答:该工程队原计划每周修建5米. 10分 19.证法一:如图1,∵ CD ,AB 是⊙O 直径, 1分∴=. 3分∵ FD =EB ,∴ =. 5分∴-=-,即=, 8分∴ ∠D =∠B . 10分图1证法二:如图1,∵ AB ,CD 是⊙O 的直径, 1分∴=. 3分∵ DF =BE ,∴=, 5分∴--=--,即=.6分∴+=+,即=,8分∴∠D=∠B.10分证法三:如图2,连结OF,OE.1分∵OF=OD=OB=OE,5分又∵DF=BE,∴△ODF≌△OBE,8分∴∠D=∠B.10分图2证法四:如图2,连结OF,OE.1分∵DF=BE,∴∠FOD=∠EOB.3分又∵OF=OD=OB=OE,7分∴△ODF≌△OBE,8分∴∠D=∠B.10分证法五:如图2,连结OF,OE.1分∵DF=BE,∴∠FOD=∠EOB.3分∵OF=OD,OE=OB,6分∴∠F=∠D,∠E=∠B,8分又∵2∠D+∠FOD=2∠B+∠EOB=180°,9分∴∠D=B.10分证法六:如图3,连结CF,AE.1分∵AB,CD是⊙O的直径,∴∠F=∠E=90°,3分∵AB=CD,DF=BE,7分∴Rt△DFE≌Rt△BEA,8分图3证法七:如图3,连结CF,AE.1分∵DF=BE,∴=.3分∵∠C=∠A.4分∵CD,AB是⊙O的直径,∴∠F=∠E=90°,6分∴∠C+∠D=∠A+∠B=90°,8分∴ ∠D =∠B . 10分 证法八:如图4,过O 点作OM ⊥FD 于M ,ON ⊥BE 于N . 1分 ∵ DF =BE ,∴ OM =ON . 5分 ∵ OD =OB ,∴ Rt △OMD ≌Rt △ONB , 8分∴ ∠D =∠B . 10分图4证法九:如图5,连结DB . 1分 ∵ OD =OB ,∴ ∠1=∠2, 2分∴=. 3分∵ DF =BE ,∴ =, 5分∴ =, 6分∴+=+,即=; 8分∴ ∠D =∠B . 10分图520.解:(1)100.5,150.5,10,25,0.25,1.00(每空1分); 6分 (2)0.25,100(每空1分); 8分 (3)(0.3+0.1+0.05)×1000=450(人). 11分 答:估计应对该校1000名学生中约450名学生提出这项建议. 12分 四、解答题(本题共3小题,其中21题7分,22题8分,23题9分,共24分)21.解:(1)∵ 点A (1,0)在抛物线n x x y ++-=52上,∴ 051=++-n ,1分 ∴ 4-=n . 2分 ∴ 抛物线的解析式是452-+-=x x y . 3分 (2)由(1)知,抛物线与y 轴交点的坐标为B (0,-4), 4分 连结AB ,则174122=+=AB . 5分∵ △P AB 为等腰三角形,点P 在y 轴正半轴上,①当AB =AP 时,∵ OA ⊥BP ,∴ OP =OB , ∴ 点P 的坐标为(0,4). 6分 ②当AB =BP 时,∵ 17=AB ,∴ 17=BP ,∴ 417-=-=OB BP OP ,∴ 点P 的坐标为(0,417-). 7分 ∴ 点P 的坐标为(0,4)或(0,417-).22.解:(1)π,2π(每空2分); 4分 (2)方法一:∵ 凸n 边形的内角和为(n -2)180°, 5分 而n 条弧的弧长的和恰为)2(21360180)2(-=-n n 个以某定点为圆心,以1为半径的圆的周长, 7分 ∴ n 条弧的弧长的和为π)2()2(211π2-=-⨯⨯n n . 8分方法二:设1A ∠,2A ∠,…,n A ∠的度数分别为1α,2α,…,n α,弧长分别为1l ,2l ,…,n l π180180π180π180π212121n n n l l l αααααα+++=+++=+++ , 5分 ∵ 180)2(21-=+++n n ααα , 6分 ∴ π)2(π180180)2(21-=-=+++n n l l l n . 7分∴ n 条弧的弧长的和为π)2(-n . 8分 23.解:(1)一; 3分(2)方法一:由题意得,一班第三棒运动员的运动图象经过(28,200),(40,300),设其解析式为11b x k y +=;二班第三棒运动员的运动图象经过(25,200),(41,300),设其解析式为22b x k y +=. 4分 ⎩⎨⎧=+=+;,30040200281111b k b k ⎩⎨⎧=+=+.,30041200252222b k b k 5分解得⎪⎪⎩⎪⎪⎨⎧-==;,310032511b k⎪⎪⎩⎪⎪⎨⎧==.,417542522b k∴ 31003251-=x y ,41754252+=x y . 6分∴ 21y y =,∴41754253100325+=-x x , 7分解得x =37. 8分 答:发令后37秒两班运动员第一次并列. 9分 方法二:观察、分析图象知,一班第三棒运动员的速度为3252840200300=--(米/秒).4分二班第三棒运动员的速度为4252541200300=--(米/秒). 5分二班的第三棒运动员比一班的第三棒运动员早出发3秒. 6分 设一班的第三棒运动员出发x 秒时追上二班运动员, 7分 得x x 325)3(425=+, 8分解得x =9,9+28=37(秒).答:发令后37秒两班运动员第一次并列. 9分五、解答题和附加题(解答题共3小题,其中24、25题各8分,26题10分,共26分;附加题5分,但全卷累计不超过150分)24.证明:如图6,连结AF ,则∠ABD =∠F .∵ ∠ADG =∠ABD ,∴ ∠ADG =∠F . 1分 ∵ DF 为⊙O 的直径,∴ ∠DAF =90°.∴ ∠ADF +∠F =90°, 2分 ∴ ∠ADG +∠ADF =∠FDG =90°. 3分 ∴ ∠DAF =∠CDE =90°. 4分 ∵CB ⊥AB ,∴ ∠CBE =90°.取EC 中点M ,连结DM ,BM ,则DM =BM =CM =EM ,即D 、E 、B 、C 在以EC 为直径的圆上. 5分 ∴ ∠ABD =∠DCE ,∴ ∠DCE =∠F . 6分 ∴ △DAF ∽△EDC , 7分 ∴CEDF DEAD =,∴ DF DE CE AD ⋅⋅=. 8分图6(一)没有直接解答问题写出探究过程. 思路一:如图6,连结AF .∵ DF 为⊙O 的直径,∴ ∠DAF =90°. 1分 ∴ ∠ADF +∠F =90°.∵ ∠ADG =∠ABD ,∠ABD =∠F ,∴ ∠ADG =∠F . 2分∴ ∠ADF +∠ADG =90°,∴ DF ⊥CG . 思路二:如图6,连结AF .∵ DF 为⊙O 的直径,∴ ∠DAF =90°. 1分 ∴ ∠ADF +∠F =90°.∵ CB ⊥AB ,∴ ∠CBD +∠ABD =90°. 2分∵ ∠ABD =∠F ,∴ ∠ADF =∠CBD . 思路三:如图7,连结BF .∵ DF 为⊙O 的直径,∴ ∠DBF =90°. 1分 ∴ ∠ABD +∠ABF =90°.∵ ∠ADG =∠ABD ,∠ADF =∠ABF ,∴ ∠ADG +∠ADF =90°,即∠GDF =90°. 2分 ∴ CG 切⊙O 于D .图7思路四:如图8,连结AF . 要证DF DE CE AD ⋅⋅=,需证CEDF DEAD =,需证△DAF ∽△EDC . 1分 需证∠F =∠DCE ,∠ADE =∠DEC .要证∠ADE =∠DEC ,需证AD ∥CE . 2分 要证∠F =∠DCE ,需证∠DCE =∠DBA .图8(二)选取①.证法一:如图8,连结AF ,则∠ABD =∠F .∵ ∠ADG =∠ABD ,∴ ∠ADG =∠F . 1分 ∵ DF 为⊙O 的直径,∴ ∠DAF =90°,∴ ∠ADF +∠F =90°,∴ ∠ADG +∠ADF =∠FDG =90°, 2分 ∴ ∠DAF =∠CDE =90°,∴ CD 是⊙O 的切线. 3分 ∴ ∠BAD =∠BDC .∵ ∠BDC =∠CEB ,∴ ∠BAD =∠CEB .∴ AD ∥EC ,∴ ∠ADF =∠DEC , 4分∴ △DAF ∽△EDC , 5分 ∴CEDFDE AD=,∴ DFDECE AD ⋅⋅=. 6分证法二:同证法一,∵ AD ∥CE ,∴ ∠ADG =∠DCE ,∴ ∠DCE =∠F . 4分 ∴ △ADF ∽△DEC , 5分 ∴CEDF DEAD =,∴ DF DE CE AD ⋅⋅=. 6分(三)选取②.证法一:如图8,连结AF .同(二)中证法一,得∠DAF =∠CDE =90°. 2分 ∵ AD ∥CE ,∴ ∠ADF =∠DEC . 3分 ∴ △DAF ∽△EDC ,∴ CEDF DEAD =,∴ DF DE CE AD ⋅⋅=. 4分 证法二:如图9,连结AF ,BF .∵ ∠ADG =∠DBA ,∠ADF =∠ABF ,∴ ∠ADG +∠ADF =∠DBA +∠ABF ,即∠GDF =∠DBF . 1分∵ DF 是⊙O 的直径,∴ ∠DBF =∠DAF =90°,∴ ∠GDF =90°,∴ ∠DAF =∠EDC =90°. 2分 ∵ AD ∥CE ,∴ ∠ADE =∠DEC . 3分 ∴ △ADF ∽△DEC ,∴CEDF DEAD =,∴ DF DE CE AD ⋅⋅=. 4分 (四)选取③.证明:如图9,∵ DF 是⊙O 的直径,∴ ∠DAF =90°.∵ ∠CDE =90°,∴ ∠DAF =∠CDE . 1分 又∵ ∠ADF =∠DEC ,∴ △ADF ∽△DEC , ∴CEDF DEAD =,∴ DF DE CE AD ⋅⋅=. 2分图925.解:(1)如图10,由题意知:)93(1,-P ,)42(2,-P ,)11(3,-P ,)00(4,P . 1分 433332222144114321P H P P H HP P H HP P H P P P P P S S S S S ∆∆---=梯形梯形四边形.11211)14(211)49(213921⨯⨯-⨯+⨯-⨯+⨯-⨯⨯=4=. 2分 44321=P P P P S 四边形. 3分图10(2)四边形211++-n n n n P P P P 的面积为4.理由:过点1-n P 、n P 、1+n P 、2+n P 分别作11--n n H P 、n n H P 、11++n n H P 、22++n n H P 垂直于x 轴,垂足分别为1-n H 、n H 、1+n H 、2+n H .设1-n P 、n P 、1+n P 、2+n P 四点的横坐标依次为x -1,x ,x +1,x +2,则这四个点的纵坐标分别为2)1(-x ,2x ,2)1(+x ,2)2(+x ,所以四边形211++-n n n n P P P P 的面积=梯形211+--n n n P H P 的面积-梯形n n n n P H H P 11--的面积-梯形11++n n n n P H H P -梯形2211++++n n n n P H H P 的面积 4分 ])2()1[(21])1([21])1[(21])2()1[(2322222222+++-++-+--++-=x x x x x x x x5分4)1()2()1(2222=+--++-=x x x x . 7分 (3)四边形211++-n n n n P P P P 的面积为4. 8分 26.实验操作,图形正确. 1分 (1)证法一:如图11,过P 点作两圆外公切线MN ,连结EF .∵ MN 为两圆的外公切线,∴ ∠NPB =∠PEF =∠A , 2分 ∴ EF ∥AB . 3分 又∵ AB C O ⊥1,∴ EF C O ⊥1.又∵ C O 1为⊙1O 的半径,∴=. 4分图11证法二:如图12,过点P 作两圆的外公切线MN ,连结CP .∵ AB C O ⊥1,C O 1为⊙1O 的半径,∴ AB 切⊙1O 于C .∴ ∠BCP =∠CEP . ∵ MN 为两圆外公切线,∴ ∠MPA =∠B =∠PCE . 2分 ∴ ∠CPE =∠CPB , 3分∴=. 4分图12证法三:如图12,过点P 作两圆的外公切线MN ,连结PC . ∵ AB C O ⊥1,C O 1为⊙1O 的半径,∴ AB 切⊙1O 于C .又∵ MN 是两圆外公切线,∴ ∠MPC =∠PCA ,∠MPE =∠B . 2分 ∵ ∠EPC =∠MPC -∠MPE ,∠BPC =∠PCA -∠B ,∴ ∠EPC =∠BPC , 3分∴=. 4分证法四:如图13,连结PC 并延长交⊙2O 于G ,连结G O 2,P O 2. ∵ P 为切点,则1O 在P O 2上.∵ C O P O 11=,∴ CP O PC O 11∠=∠.又∵ G O P O 22=,∴ GP O PG O 22∠=∠,∴ GP O CP O 21∠=∠,∴ G O C O 21//. 2分 ∵ AB C O ⊥1,∴ AB G O ⊥2,∴ =,∴∠APG =∠BPG , 3分∴=. 4分图13探究(2)结论:PE BF CE⋅=2. 5分证法一:如图14,连结CF ,∴ AB 切⊙1O 于C ,∴ ∠BCF =∠CPB ,∵ ∠CPB =∠CPE ,∴ ∠BCF =∠CPE . 6分 ∵ ⊙1O 是四边形ECEP 的外接圆,∴ ∠CFB =∠CEP . 7分 ∴ △BCF ∽△CPE ,∴ PECF CEBF =. 8分又∵ =,∴ CE =CF , 9分 ∴PECE CEBF =,∴ PE BF CE⋅=2. 10分图14证法二:如图14,连结CF .∵ MN 是两圆的外公切线,∴ ∠MPA =∠PCE =∠B . 6分∵ ⊙1O 是四边形ECFP 的外接圆,∴ ∠CFB =∠CEP . 7分 ∴ △CBF ∽△PCE ,∴ PECF CEBF =, 8分又∵ =,∴ CE =CF . 9分∴ PE BF CE⋅=2. 10分证法三:如图14,连结CF .∵ EF ∥AB ,∴ BFPF AEPE =,∴ BF PE PF AE ⋅⋅=.6分∵ ⊙1O 是四边形ECFP 的外接圆,∴ ∠AEC =∠PEC .∵ AB 切⊙1O 于C ,∴ ∠ACE =∠APC ,又∵ ∠APC =∠CPB ,∴ ∠ACE = ∠CPB .∴ △AEC ∽△CEP , 7分 ∴PFCECF AE=,∴ CF CE PF AE ⋅⋅=,∴ BF PE CF CE ⋅⋅=. 8分∵ =,∴ CE =DF . 9分∴ BF PE CE⋅=2.10分 证法四:如图15,连结CF .∵ AB 切⊙1O 于C ,∴ ∠PCB =∠PEC ,又∵ ∠BPC =∠CPB , 6分 ∴ △PEC ∽△PCB ,∴BCCE PCPE =,∴PCBC PECE =, 7分∵ AB 切⊙1O 于C ,∴ ∠BCF =∠CPB ,又∵ ∠B =∠B ,∴ △CFB ∽△PCB , 8分 ∴ PC CF BCBF =,∴ PCBC CFBF =,∴CFBF PECE =,∵=,∴ CE =CF , 9分∴ BF PE CE⋅=2. 10分图15附加题:图正确,结论:BF PE CE⋅=2. 1分证法一:如图16,过点P 作两圆的内公切线MN ,连结CF ,EF ,PC . ∵ BC C O ⊥1,C O 1为⊙1O 的半径,∴ BC 切⊙1O 于C , ∵ MN 是两圆的内公切线,∴ ∠MPE =∠EFP ,∠NPA =∠B ,又∵ ∠MPE =∠NP A ,∴ ∠EFP =∠B , 2分∴ EF ∥BC ,∴ EF C O ⊥1,∴=,∴ CE =CF .∴ ∠B =∠EPF ,∠EFP =∠ECP ,∴ ∠B =∠ECP .又∵ ∠PEC =∠PFC ,∴ △EPC ∽△FCB , 4分 ∴CFPE BFCE =,∴ CEPE BFCE =,∴ BF PE CE⋅=2. 5分图16证法二:如图16,过点P 作两圆的内公切线MN ,连结CF ,EF ,CP . ∵ MN 是两圆的内公切线,∴ ∠MPE =∠EFB ,∠NPA =∠B ,∵ ∠MPE =∠NP A ,∴ ∠EFB =∠B . 2分 ∵ CB C O ⊥1,C O 1是⊙1O 的半径, ∴ BC 切⊙1O 于C ,∴ ∠PCB =∠PFC .∵ ∠FEC =∠FPC =∠PCB +∠B ,∠EFC =∠PFC +EFB ,∴ ∠FEC =∠EFC , ∴ CF =CE . 3分 余下同证法一. 5分 证法三:如图16,过点P 作两圆的内公切线MN ,连结EF ,CF ,CP . ∵ CB C O ⊥1,C O 1是⊙1O 的半径,∴ CB 是⊙1O 的切线.∴ ∠PCN =∠CPN ,∠B =∠APN . 2分 ∴ ∠PCN +∠B =∠CPN +∠APN ,∴ ∠APC =∠CPF .又∵ 四边形CPEF 内接于⊙1O ,∴ ∠APC =∠EFC ,又∵ ∠CPF =∠FEC , ∴ ∠EFC =∠FEC ,∴ CE =CF . 3分 余下同证法一. 5分。
2008 大连市中考试题
2008 大连市中考试题一、单选:1. Liu Changchun is _____ first Chinese to join the Olympics. A. a B. an C. the D./2. New York and Washington D.C are good places to visit ___ May or October. A. from B. at C. in D. on3. My father is a teacher. ______ saved four students from a failing building in the earthquake(地震).A. HeB. IC. sheD. You4. As a ____ , he tries to give the firsthand information to the public as soon as possible.A. secretaryB. passengerC. professorD. reporter5. By studying hard and not ____, you will succeed. A. giving up B. hurrying up C. progessor D. reporter6. -=May I invite you to have dinner this Friday? -- _______.A. Yes, pleaseB. Just have a lookC. Never mindD. trying out7. _____ lovely day! Let’s go for a walk. A. What B. What a C. How D. How a8. Li Ming is the photographer ____ won the Photo Competition last month. A. whose B. which C. who D. who9. It is ____ that some young people in China are starting to show interest in Peking Opera.A. crazyB. sadC. usefulD. nice10. It’s still early. You _____ worry about the time. A. can’t B. wouldn’t C. needn’t D. couldn’t11. – Thank you for your help. -- ______.A. That’s great.B. You’re welcome.C. I’m sure of thatD. I’m afraid not.12.The operation on Sandy’s broken leg ____ three hours. A. lasted B. spent C. included D. cost13. Having afternoon tea is an English ____. A. ceremony B. tradition C. menu D. food14. Tony likes listening to music, ____ he hates practising the vilion. A. but B. so C. and D. or15. Pirates of the Caribbean is one of ______ films that I have ever seen.A. very excitingB. more excitingC. much more excitingD. the most exciting16. – Could you tell me ____? - It’s just opposite the road.A. how can I get to the bus stationB. where the bus station isC. how I could get to the bus stationD. where was the bus station17. Travellers _____ to use mobile phones while flying.A. don’t allowB. are n’t allowedC. won’t allowD. didn’t allow18. Lucy uses her pocket money to buy books ____ she loves reading.A. ifB. althoughC. becauseD. until19. Mr Zhang is a teacher of rich experience. He ____ English for 20 years.A. has taughtB. will teachC. teachesD. taught20. To protect the enviroment, most supermarkets in China stopped ____ free plastic bags.A. to sendB. sendingC. to provideD. providing二、完形填空One day Mark Twain was asked whether he could remember the first money he made.He thought a while and then 21_____, “Yes. It was at school. The pupils in those days never 22______ the things of the school. They often broke the windows and glassed. There was a 23____ that any boy who broke the glass would be 24____ in front of the whole school, or have to pay five dollars.”“One afternoon I was playing football, when 25____ my ball hit the window. I ran over and found 26_____ glass broke into pieces. I could do 27____ but tell my father I had made the mistake, and that I should pay the money or be beaten before the whole school. He agreed to give me the money 28____ I could hand it over to the head teacher. But 29 ___ giving me the money, he took me upstairs and gave me a good beating.”“But having had one beating and got used to it, I decided I would accept another beating at school and 30____ the five dollars. So that’s what I did. That was the first money I ever made.”A B C D21. promise answered explained agreed22. took care of did harm(危害) to threw away picked up23. test fact rule goal24. praised(表扬) welcomed bitten beaten25 suddenly carelessly luckily carefully26. it its which whose27. nothing something everything anything28. even though rather than ever since so that29. instead thanks to before without30. accept refuse keep return三、阅读理解:A blind boy sat on the steps of a building with a hat by his feet. He held up a sign: “I am blind, please help.” There were only a few coins in that hat.A man was walking by. He took the sign from the boy, turned it around, and wrote some words. He put the sign back, so everyone would see the new words when they walked by. Soon the hat began to fill up (装满) . A lot more people were giving money.That afternoon the man came again to see how things were. The boy knew him from his footsteps and asked,: “What did you write?”The man sad, “I said what you said, but in a different way.” What he had written was “Today is a beautiful day and I cannot see it.”Both signs said that the boy was blind. But the first sign simply told people to help by putting some money in the hat. The second sign told people that they were able to enjoy the beauty of the day, but the blind boy could not. The second sign was more helpful.31. The blind boy sat on the steps of building because he ____.A. lost his moneyB. was waiting for a manC. wanted to get help from jothersD. couldn’t see the sign on the building32. When a man saw the sign held up by the blind boy, he ____.A. drew some coins on itB. put a few coins in the hatC. turned it around and walked awayD. try to do things in a different way33. The boy could recognize the man from _______.A. his foootstepsB. his voiceC. his wordsD. his accent34. We can infer(推断) from the second sign that we should _______.A. give more money to the blindB. be thankful for what we haveC. enjoy ourselves during the dayD. try to do things in a different way35. The best title of the passage is “ ______”.A. I am blind: please helpB. There is always a better wayC. Giving is better than receivingD. Today is a beautiful day and I can’t see itBDo you want to become an astronaut? If yoku want to be one of the few people to experience the thrill of lilft-off(发射), see the Earth from on high and float (漂浮) in a spacecraft, then how do you go about it ? Well:First: You must really want to become an astronaut as it takes many years of study and work before you even begin your astronaut training. Most astronauts begin when they are between 27 and 37.Second : You need to be clever enough to attend a university to study engineering, medicine or one of the sciences. Many astronauts also learn to be pilotys in their country’s air force(空军).Third: Astronauts come from many different countries, so they need to speak English so that they can all talk to one another.Fourth: You must be healthy as astronaut training can be very tiring.Lastly: On a spacecraft astronauts live and work in a very small space, so you need to get on well with people.Are you still interested? If so, maybe you will become one of the men and women that orbit the Earth in a spacecraft, walk in space or visit Mars. See you in space!36. The underlined word “thrill” may mean the following feelings EXCEPT ______.A. excitementB. dangerC. fearD. pleasure37. Usually the astronaut training starts when they are ______.A. at the universityB. in the rmyC. between 27 and 37D. older than 3738. From the passage, we know tht all astronauts need to _____.A. study in different countriesB. be cleverer than ordinary peopleC. be pilots I nthe air force at firstD. study engineering, medicine or one of the sciences39. Astronauts coming from different countries use ____ to talk to each other.A. actionB. gesturesC. EnglishD. French40. If you are on a spacecraft, you need to learn how to ____.A. wak and fly in spaceB. orbit the Earth or visit MarsC. live and work together as a teamD. live and work in a very small spaceCAre you spending two days in Tokyo? Are you moving to Melbourne? No matter where you’re going or how long you’re staying, keep reading! These tips() will help you make the most of any city adventure.Before you arriveRead a city guidebook. If you don’t want to buy one, just look through the guidebooks in a store. They can give you some advice on how to plan your trip.Search the Internet. Websites such as Citysearch, com and provide information on cities around the world. Blogs() can also give you a chance to learn from others’ travel expericeces.Doing research before you arrive will help you experience the city’s claim to fame(). Whether it’s a city symbol, a shopping area, or a river- you should see it.When you arriveIf possible, pick up a free city map at the airport, train station or your hotel. Visit the city’s tourism office, which will provide other valuable information. Sometimes local() newspapers or posters offter tours or other services.Carry the hotel’s business card or write down the address and phone number. Take note of the neighborhood around your hotel. It will be helpful when you return.Ask a local person for advice. Many cities have treasures that most tourists don’t know about. A local can direct you to a wonderful but less famous restaurant, park or museum.Finally, be a dventurous! Some of the best things that a city has to offter can be found by mistake. If you’r not afraid to get lost, you’ll see more- and you’ll have a better time!41. When you plan a city tour, you are advised to ______.A. get a city mapB. ask a local personC. read a city guidebookD. go to a tourism office42. According to the passage, we can get others’ travel experiences from _____.A. blogsB. postersC. local newspapersD. city guidebooks43. Doing research before starting a trip is helpful for us _____.A. to travel around the cityB. to visit less faomous placesC. to find treasures in the cityD. to experience the city’s claim to fame44. From the passage we know that a free city map may be found ____.A. at the airportB. on the InternetC. at a bookstoreD. in a shopping area45. The article is mainly written to give us some advice on ______.A. how to explore a cityB. how to plan a city adventureC. how to search for information on a cityD.how to be more adventurous in a city tourD.Every year, thokusands of students choose to study in anoter country. More than 30 percent of these students go to the United States. Around 15 percent go to Italy, and 10 percent go to both England and Germany . A little less than 10 percent go to Australia, and around 5 percent go to Canada.No matter where a student chooses to study, there are some things universities around the world need. First, allstudents must gaduate from high school before they can apply(申请) to a university. Most universities also need some kind of test for students to enter the university. Universities in the United States, Australis, and Canada usually need some kind of standardized(标准化的) exam, such as the SAT in the United States. Students who do not come from English- speaking countries also must take a test such as the TOEFL in the United States and Canada to show they know enough English to study in English. England and Australia require(要求) students to take the IELTS.IN most countries, students must apply to each university they hope to go to. However, students applying to universities in England can use one form to apply to six universities at one time through the British Council(英国文化学会). Many students like this because it can save them a lot of time and money. For universities in other countries, students must fill in different forms for each university and pay a fee(费用) with each application.46. According to the passage, ____ is the most popular country where foreign students would like to choose to study inEurope.A. the USAB. ItalyC. GermanyD. England47.According to the passage, those who want to study abroad can’t apply to any university until _____.A. they get their passportsB. they choose the right countryC. they graduate from high schoolD. they pass the TOEFL, or the LELTS48. The underlined word “SAT” may stand for _____ in the USA.A. a universityB. a kind of testC. a social groupD. a school organization49. If Chinese students want to apple to a university in Australia, they have to _____.A. take TOEFLB. take the LELTSC. know enough EnglishD. study English first50 One of the advantages for students applying to universities in England is that ______.A. it saves time and moneyB. they needn’t pay for any applicattionC. they can choose six countries each timeD. they have sic chances ot go othr countries四、情景交际:B: Yes. _51_____________.A: Oh, we’ve got some dresses here. __52______________B:OK.A: All the things are on sale (降价出售) today 53________.B: Wonderful! It’s the right colour for me. May I try it on?A: _54______.B: Great! It fits me well. By the way, do you have the right shoesto match it?A: Sure. Take a look at the amazing shoes.B: That’s great! _55________.A: 298 yuan.B: That’s fine. I’ll take them.五、完形填空(二)(26分,每题2分)because what bill service invites ively food usually Dining out in the West and dining out China are two very different experiences. In the West, people eat very personally. They do not often share their 56____. When a plate arrives in a western restaurant, everything on it is 57_____ for one person. The person wants to know exactly 58____ and how much they are going to eat. This is not just 59____ they have different tastes, it’s also a matter of cost. Unless a person 60_____ everyone as a treat(款待),each dinner usually only pays for his or her share.Yet people often tip(给小费)the waiters. You tip on how good you thought the 61_______ was. But it’s usually about ten percent of the 62_______.In China, food is passed around and shared. That makes eating out more 63______. Yet paying is not shared.Westerners think the way people in China sometimes argue (争论) over who pays the bill seems very strange!B)The 2004 Olympic Games were held in Athens in August. The Games were watched by four billion people all over the world. This was the biggest number of people ever to 64________ a sports event. More than 11,000 sportsmen and sportswomen from 202 countries took part in the Games, with a larger number of sportswomen 65________ ever before.The largest number of medals was won by America, with 35 gold mecals. China came second with 32 gold medals. Russia was 66_______, with 27 gold medals.When the Chinese Olympic sportsmen and sportswomen 67_________ to China after the Games, many people came to see them at the airport. They were very proud of their heroes. The sportsmen and sportswomen were 68_______ very proud. “My country, I love you!” said Liu Xiang, the winner of the hurdeing gold medal.At the end of the 2004 Olympic Games, the Olympic flag was taken to Beijing for the 2008 Games do not stop! 六、阅读理解:(16分)Florence Nightingale was born in a rich family. (74) When she was young, she took lessons in music and drawing, and read great books. She also traveled a great deal(大量的) with her parents.As a child she felt that visiting sick people was both a duty and a pleasure. She enjoyed helping them.At last her mind was made up, “I’m going to be a nurse.” She decided.“Nursing isn’t the right work for a lady,” her father told her.“Then I will make it so.” she smiled. And then she went to learn nursing in Germany and France.During the Crimean War in 1854, she and a team of thirty- eight nurses went to the fornt hospitals. What they saw there was terrible. Many soldiers died because the hospitals were dirty. But the brave nurses went to work hard to make the hospital clean and stop soldiers dying. Florence use her own money and some from friends to buy clothes, beds medicines and food for the men . Her only pay was smiles from thedying soldiers. But they were more than enough for this kind woman.After the war she returned to England69. What did Nightingale love doing when she was a child?70. What id her fataher say when Nightingale decided to be a nurse?71. How long did Nightingale work in the front hospitals?72. Did Nightingale make a lot of money during the Crimean War?73. Why do we honor nurses today?74将划线句子译成汉语。
2008大连市中考数学试题及答案
2008年大连市䌜毕业升学统一考试旅顺口区试测(一)数学本试卷1~8页,共150分,考试时间120分钟。
一、选择题(本题8小题,每小题3分,共24分)说明:将下列各题唯一正确的答案代号A、B、C、D填到题后的括号内。
1.如图,小明用手盖住的点的坐标可能为( )A.(2,3)B.(2,-3) C.(-2,3) D.(-2,-3)2.下图为各届夏季奥运会的会徽图案,其中是轴对称图形的是()A.B.C.D.3.下列运算中,正确..的是( )A.24=B.623-=-C.22)(abab=D.2523aaa=+4.如图所示是某校九年级学生到校方式的条形统计图,根据图形可得出步行人数占总人数的( )A.60%B.50%C.30%D.20%5.已知⊙O1的半径为5cm,⊙O2的半径为3cm,圆心距O1O2=2,那么⊙O1与⊙O2的位置关系是()A.相离B.外切C.相交D.内切6.测得某人的一根头发直径约为0.000 072 85米,用科学记数法表示为( )A.7285×10-8米B.7.285×10-5 米C.0.7285×14-4 米D.0.7285×10-5米7.均匀地向一个如图所示的容器中注水,最后把容器注满,在注水过程中水面高度h随时间t变化的函数图象大致是().2008年北京1992年巴塞罗那1980年莫斯科1972年慕尼黑yxO二、填空题(本题共8小题,每小题3分,共24分)说明:将答案直接填在题后的横线上。
9.如果某天中午气温是2°C ,到了傍晚气温下降了5°C ,那么傍晚的气温是__________C°.1011个地区当天最高气温(℃)统计如下表:那么这些城市当天的最高气温的中位数和众数分别是________,_________.11.不等式组21040x x ->⎧⎨-≥⎩的解集是________________.12.小明的身高是1.7m ,他的影长是2m ,同一时刻学校旗杆的影长是10m ,则旗杆的高是_________m .13.如图,P 为正方形ABCD 内的一点,△ABP 绕点B 顺时针旋转得到△CBE ,则△BPE 是 三角形.14.矩形的面积为2,一条边长为x ,另一条边长为y ,则y 与x 的函数关系式为(不必写出自变量取值范围)____________________.15.如图,△ABC 后的图形是△A ′B ′C ′,其中C 与C ′是对应点,请画出平移后的三角形△A ′B ′C ′.16.已知二次函数22y x x m =-++的部分图象如图所示,则关于x 的一元二次方程220x x m -++=的解为 .EPDCBA16题图15题图13题图三、解答题(本题共4小题,每题10分,共40分)17.已知22212211x x y x x x x x -=÷---++,当x 为何值时,y 的值为12.18.红星超市07年十月份的营业额为4万元,第四季度的总营业额是13.24万元,求十一、十二月份平均每月增长的百分率.19.如图,在4×3的正方形网格中,△ABC 与△DE C 的顶点都在边长为1的小正方形的顶点上。
2008年辽宁省大连市数学中考真题(word版含答案)
题号 分数 本试卷 1~8 页,满分 150 分.考试时间 120 分钟. 阅卷人 得分 一、选择题(本题共 8 小题,每小题 3 分,共 24 分) 说明:将下列各题惟一正确的答案代号 A、B、C、D 填到题后的括号内. ) 一 二 三 四
学
五 总分
1.如图 1,下列各点在阴影区域内的是 ( A. (3,2) B. (-3,2) C. (3,-2) D. (-3,-2) 2.下列各式运算正确的是 ( ) A. 3mn 3n m C. x 3 B. y 3 y 3 y D. a · a = a
乙 25% 丙 25%
图2
5.已知两圆的半径分别为 6 和 8,圆心距为 7,则两圆的位置关系是 ( ) A.外离 B.外切 C.相交 D.内切 6.某鞋店试销一新款女鞋,试销期间对不同颜色鞋的销售情况统计如下表: 颜色 销售量(双) 黑色 60 棕色 50 白色 10 红色 15 )
鞋店经理最关心的是哪种颜色鞋最畅销,则对鞋店经理最有意义的统计量是( A.平均数 B.众数 C.中位数 D.方差 7.如图 3,用一个平面去截长方体,则截面形状为 ( )
19.如图 9,PA,PB 是⊙O 的切线,点 A,B 为切点,AC 是⊙O 的直径,∠ACB=70°. 求∠P 的度数.
A
O
P
C
B
图9
20.六一期间,某公园游戏场举行“迎奥运”活动.有一种游戏的规则是:在一个装有 6 个红球和若干个白球(每个球除颜色外其他都相同)的袋中,随机摸一个球,摸到一个 红球就得到一个奥运福娃玩具. 已知参加这种游戏活动为 40000 人次, 公园游戏场发放 的福娃玩具为 10000 个. (1)求参加一次这种游戏活动得到福娃玩具的频率; (2)请你估计袋中白球接近多少个?
2008年各地中考数学试题精选 辽宁省
2008年各地中考数学试题精选辽宁省
侯明辉
【期刊名称】《数理天地:初中版》
【年(卷),期】2008(000)009
【总页数】3页(P9-11)
【作者】侯明辉
【作者单位】辽宁省岫岩满族自治县教师进修学校数学研究室
【正文语种】中文
【中图分类】G634.6
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2008年辽宁省中考数学几何题(含答案)
2008年辽宁省中考数学几何题 2008年辽宁省中考数学几何选择题(08辽宁沈阳)2.如图所示的几何体的左视图是( A )(08辽宁沈阳)6.若等腰三角形中有一个角等于50,则这个等腰三角形的顶角的度数为( D ) A .50B .80C .65 或50D .50 或80(08辽宁沈阳)8.如图所示,正方形ABCD 中,点E 是CD 边上一点,连接AE ,交对角线BD 于点F ,连接CF ,则图中全等三角形共有( C ) A .1对 B .2对 C .3对 D .4对(08辽宁大连)5.已知两圆的半径分别为6和8,圆心距为7,则两圆的位置关系是 ( C ) A .外离 B .外切 C .相交 D .内切(08辽宁大连)7.如图3,用一个平面去截长方体,则截面形状为( B )(08辽宁大连)8.图4的尺规作图是作 ( A )A .线段的垂直平分线B .一个半径定值的圆C .一条直线的平行线D .一个角等于已知角正面第2题图A .B .C .D .AD CEF B 第8题图 图4D C B A 图 3(08辽宁十二市)2.如图1,直线12l l ∥,l 分别与12l l ,相交,如果2120∠=,那么1∠的度数是( C ) A .30B .45C .60D .75(08辽宁十二市)4.图2是由几个相同的小正方体搭成的一个几何体,它的俯视图是( D )(08辽宁十二市)5.下列命题中正确的是( A ) A .两条对角线互相平分的四边形是平行四边形 B .两条对角线相等的四边形是矩形 C .两条对角线互相垂直的四边形是菱形D .两条对角线互相垂直且平分的四边形是正方形(08辽宁十二市)8.图3是对称中心为点O 的正八边形.如果用一个含45角的直角三角板的角,借助点O (使角的顶点落在点O 处)把这个正八边形的面积n 等分. 那么n 的所有可能的值有( B )A .2个B .3个C .4个D .5个图2A .B .C .D .ll 1l 212 图1 图32008年辽宁省中考数学几何填空题(08辽宁沈阳)9.已知A ∠与B ∠互余,若70A ∠=,则B ∠的度数为 .20(08辽宁沈阳)11.已知ABC △中,60A ∠=,ABC ∠,ACB ∠的平分线交于点O , 则BOC ∠的度数为 .120(08辽宁沈阳)12.如图所示,菱形ABCD 中,对角线AC BD ,相交于点O ,若再补 充一个条件能使菱形ABCD 成为正方形,则这个条件是 (只填一个条件即可).90BAD ∠= (或AD AB ⊥,AC BD =等)(08辽宁沈阳)14.如图所示,某河堤的横断面是梯形ABCD ,BC AD ∥,迎水坡AB 长13米,且12tan 5BAE ∠=,则河堤的高BE 为 米.12 (08辽宁大连)10.如图5,若△ABC ∽△DEF ,则∠D 的度数为______________.30 (08辽宁大连)13.如图7,P 是正△ABC 内的一点,若将△PAC 绕点A 逆时针旋转到 △P ′AB ,则∠PAP ′的度数为________.60(08辽宁大连)15.如图8,在梯形ABCD 中,AD ∥BC ,E 为BC 上一点,DE ∥AB ,AD 的 长为1,BC 的长为2,则CE 的长为___________.1(08辽宁十二市)12.如图4,D E ,分别是ABC △的边AB AC ,上的点,DE BC ∥,2ADDB=,则:ADE ABC S S =△△ .4:9(08辽宁十二市)14.一个圆锥底面周长为4πcm ,母线长为5cm ,则这个圆锥的侧面积是 .210cm π(丢单位扣1分)AE CD B 图4A B O第12题图 B C D A 第14题图 P′PC BA 图 7图 8E DA B C30°F D CB A 图 52008年辽宁省中考数学几何解答题(08辽宁沈阳)20.如图所示,在66⨯的方格纸中,每个小方格都是边长为1的正方形,我们称每个小正方形的顶点为格点,以格点为顶点的图形称为格点图形,如图①中的三角形是格点三角形.(1)请你在图①中画一条直线将格点三角形分割成两部分,将这两部分重新拼成两个不同的格点四边形,并将这两个格点四边形分别画在图②,图③中; (2)直接写出这两个格点四边形的周长.20.解:(1)答案不唯一,如分割线为三角形的三条中位线中任意一条所在的直线等.·········· 2分拼接的图形不唯一,例如下面给出的三种情况:图①~图④,图⑤~图⑦,图⑧~图⑨,画出其中一组图中的两个图形. ······· 6分 (2)对应(1)中所给图①~图④的周长分别为4+8,4+4+ 图⑤~图⑦的周长分别为10,8+8+图⑧~图⑨的周长分别为2+4+ ··········· 10分图① 第20题图图②图③ 图⑤ 图⑥ 图⑦图⑧ 图⑨图① 图② 图③图④(08辽宁沈阳)21.如图所示,AB 是O 的一条弦,OD AB ⊥,垂足为C ,交O 于点D ,点E 在O 上.(1)若52AOD ∠=,求DEB ∠的度数; (2)若3OC =,5OA =,求AB 的长.21.解:(1)OD AB ⊥ , AD DB∴= ··················· 3分 11522622DEB AOD ∴∠=∠=⨯=····················· 5分 (2)OD AB ⊥ ,AC BC ∴=,AOC △为直角三角形, 3OC = ,5OA =,由勾股定理可得4AC === ··············· 8分28AB AC ∴== ···························· 10分(08辽宁沈阳)25.已知:如图①所示,在ABC △和ADE △中,AB AC =,AD AE =,BAC DAE ∠=∠,且点B A D ,,在一条直线上,连接BE CD M N ,,,分别为BE CD ,的中点. (1)求证:①BE CD =;②AMN △是等腰三角形.(2)在图①的基础上,将ADE △绕点A 按顺时针方向旋转180,其他条件不变,得到图②所示的图形.请直接写出(1)中的两个结论是否仍然成立;(3)在(2)的条件下,请你在图②中延长ED 交线段BC 于点P .求证:PBD AMN △∽△.25.证明:(1)①BAC DAE ∠=∠ BAE CAD ∴∠=∠AB AC = ,AD AE = ABE ACD ∴△≌△BE CD ∴=································ 3分 ②由ABE ACD △≌△得ABE ACD ∠=∠,BE CD =M N ,分别是BE CD ,的中点,BM CN ∴=················ 4分 又AB AC = ABM ACN ∴△≌△第21题图C E ND A BM图① C A EM B D N 图② 第25题图AM AN ∴=,即AMN △为等腰三角形 ··················· 6分(2)(1)中的两个结论仍然成立. ······················ 8分 (3)在图②中正确画出线段PD由(1)同理可证ABM ACN △≌△ CAN BAM ∴∠=∠ BAC MAN ∴∠=∠ 又BAC DAE ∠=∠MAN DAE BAC ∴∠=∠=∠ AMN ∴△,ADE △和ABC △都是顶角相等的等腰三角形 ·········· 10分 PBD AMN ∴∠=∠,PDB ADE ANM ∠=∠=∠PBD AMN ∴△∽△··························· 12分(08辽宁大连)19.如图9,PA 、PB 是⊙O 的切线,点A 、B 为切点,AC 是⊙O 的直径,∠ACB = 70°.求∠P 的度数.(08辽宁大连)22.水平地面上的甲、乙两楼的距离为30米,从甲楼顶部测得乙楼顶部的仰角为30°,测行乙楼底部的俯角为45°.⑴请你画出测量示意图(大楼的长、宽忽略不计); ⑵求甲、乙两楼的高度.(08辽宁大连)25.点A 、B 分别是两条平行线m 、n 上任意两点,在直线n 上找一点C ,使BC = kAB ,连结AC ,在直线AC 上任取一点E ,作∠BEF =∠A BC ,EF 交直线m 于点F . ⑴如图15,当k = 1时,探究线段EF 与EB 的关系,并中以说明;说明:①如果你经过反复探索没有解决问题,请写出探索过程(要求至少写三步);②在完成①之后,可以自己添加条件(添加的条件限定为∠ABC 为特殊角),在图16中补全图形,完成证明(选择添加条件比原题少得3分).⑵如图17,若∠ABC = 90°,k ≠1,探究线段EF 与EB 的关系,并说明理由.图 9图 17图 16图 15A E BC F n m m n n mF EABC(08辽宁十二市)18.如图8所示,在网格中建立了平面直角坐标系,每个小正方形的边长均为1个单位长度,将四边形ABCD 绕坐标原点O 按顺时针方向旋转180后得到四边形1111A B C D . (1)直接写出1D 点的坐标;(2)将四边形1111A B C D 平移,得到四边形2222A B C D ,若2(45)D ,,画出平移后的图形.(友情提示:画图时请不要涂错阴影的位置哦!)18.解:(1)1(31)D ,······························ 2分 (2)2A ,222B C D ,,描对一个点给1分. ·················· 6分 画出正确图形(见图1) ·························· 8分(08辽宁十二市)20.如图10,AB 为O 的直径,D 为弦BE 的中点,连接OD 并延长交O 于点F ,与过B 点的切线相交于点C .若点E 为 AF 的中点,连接AE . 求证:ABE OCB △≌△.图1图8图10ODB CF EA20.解:(1)证明:如图2. AB 是O 的直径.90E ∴∠=···················· 1分 又BC 是O 的切线,90OBC ∴∠=E OBC ∴∠=∠ ·················· 3分OD 过圆心,BD DE =, EFFB ∴= BOC A ∴∠=∠. ····························· 6分 E 为AF 中点, EF BF AE ∴==30ABE ∴∠= ······························ 8分 90E ∠=12AE AB OB ∴== ···························· 9分 ABE OCB ∴△≌△. ·························· 10分(08辽宁十二市)23.如图13,某数学兴趣小组在活动课上测量学校旗杆高度.已知小明的眼睛与地面的距离()AB 是1.7m ,看旗杆顶部M 的仰角为45;小红的眼睛与地面的距离()CD 是1.5m ,看旗杆顶部M 的仰角为30 .两人相距28米且位于旗杆两侧(点B N D ,,在同一条直线上). 请求出旗杆MN 的高度.1.41.7,结果保留整数)23.解法一:解:过点A 作AE MN ⊥于E ,过点C 作CF MN ⊥于F , ··········· 1分 则 1.7 1.50.2EF AB CD =-=-= ······················ 2分 在Rt AEM △中,90AEM ∠=,45MAE ∠=AE ME ∴= ······························· 3分 设AE ME x ==(不设参数也可)0.2MF x ∴=+,28FC x =- ········· 5分M N B A D C 30° 45° 图13 图 2ODBCF EAMNB A DC 30° 45° 图5 E F在Rt MFC △中,90MFC ∠= ,30MCF ∠=tan MF CF MCF ∴=∠0.2)3x x ∴+=-············· 7分 10.0x ∴≈12MN ∴≈································ 9分 答:旗杆高约为12米. ·························· 10分解法二:解:过点A 作AE MN ⊥于E ,过点C 作CF MN ⊥于F , ······· 1分 则 1.7 1.50.2EF AB CD =-=-= ······················ 2分 在Rt AEM △中,90AEM ∠=,45MAE ∠=AE ME ∴=设AE x =,则0.2MF x =+ ························ 3分在Rt MFC △中,90MFC ∠=,30MCF ∠=tan 600.2)CF MF x ==+ ······················· 5分BN ND BD +=0.2)28x x ∴+= ··························· 7分解得10.2x ≈12MN ∴≈································ 9分 答:旗杆高约为12米. ·························· 10分 (注:其他方法参照给分)。
2008年大连市初中毕业升学统一考试试测(二)word录入含完整答案与评分标准
图3 2008年大连市初中毕业升学统一考试试测(二)数 学则与□质量相等的是( )A .○B .○○C .○○○x -4 -3 -2 -1 y -1 -2 -3 -4x -4 -3 -2 -1 y -9 -6 -3 0表1 表2ABOC A′B′图5图7EDCBA图8D .○○○○7.如图5,跷跷板的支柱OC 与地面垂直,点O 是AB 的中点,AB 可以绕着点O 上下转动.当A 端落地时,∠OAC =20°, 那么横板上下可转动的最大角度(即∠A′OA )是( )A .40°B .30°C .20°D .10°8.图6是正方体分割后的一部分,则它的另一部分为 ( ) 二、填空题(本题共8小题,每小题3分,共24分) 说明:将各题结果直接填在题后的横线上.9.甲地的海拔高度为-5米,乙地比甲地高3米,则乙地的海拔高度为 米. 10.函数2+=x y 中,自变量x 的取值范围是 .11.四边形的内角和为_____________. 12.化简aa 13-结果为 . 13.一只小狗在如图7的方砖上走来走去,最终停在阴影方砖上的机会是 . 14.画直线1l 和直线2l 分别列表1、2则直线1 和直线2交点纵坐标为 .15.如图8,等腰直角△ABC 绕点A 按逆时针方向旋转60°后得到△ADE , 且AB =1,那么EC 的长为 .16.举出你学过的三个中心对称图形 , , . 三、解答题(本题共4小题,其中17、18题各9分,19题10分, 20题12分,共40分)17.轮船顺水航行4千米所需的时间和逆水航行3千米所需的时间相同.已知水流的速度是3千米/时,求轮船在静水中的速度.阅卷人 得分 阅卷人 得分A BD30° E 图9 C1 03245课外活动次数18.请补充下表空白部分根据上表中的数据,试比较12+x 与22+x 的大小,并运用你学过的整式知识证明你的结论.19.如图9,在距旗杆27m 之处,用测角器 测得旗杆顶点B 的仰角为30°,已知测角器的高AE 为1.5米,求旗杆的高BD 的长.20.为了了解学生课外活动的情况,抽查了某校甲、乙两个班的部分学生,了解他们在星期一至星期五参加课外活动的次数情况,结果如下:⑴在这次抽查中,甲班被抽查了 人,乙班被抽查了 人; ⑵请估计甲班和乙班学生参加课外活动的平均次数(要有解答过程);⑶根据以上信息,用你学过的知识,估计甲、乙两班在开展课外活动方面哪个班级更好一些? 答 ;⑷从图10中你还能得到哪些信息?(写出一个即可)图11图12四、解答题(本题共3小题,21、22题各10分,其中23题8分,共28分)21.已知直线y kx b =+经过点(0,-2)和点(-2,0).⑴求直线的解析式;⑵在图11中画出直线,并观察y >1时,x 的取值范围(直接写答案)22.如图12,点A 是函数2(0)y x x=>图象上任意一点,过A 点分别作x 、y 的平行线交函1(0)y x x =>图象于点B 、C ,过C 点作x 轴的平行线交函数2y x =图象于点D .⑴设A 点横坐标为a ,试用a 表示B 、C 点坐标;⑵求四边形ABCD 的面积.A′C′B′F ED CB A图1323.如图13,直线DE 与直线DF 交于点D ,△ABC 与△A′B′C′关于DE 对称.⑴作△A′B′C′关于直线DF 对称的△A″B″C″;⑵试探索∠BDB″与∠EDF 之间的关系,并加以证明.图14五、解答题和附加题(本题共3小题,24、25题各10分, 26题14分,共34分,附加题附加题5分,但全卷累积得分不超过150分,附加题较难,建议........考生最后答附加题........)24.如图14,抛物线2y x =上四点A 、B 、C 、D ,AB ∥CD ∥x 轴,AB 为2,点D 的纵坐标比点A 的纵坐标大1. ⑴求CD 的长;⑵如图15,若将抛物线“2y x =”改为抛物线“2289y x x =-+”,其他条件不变,求CD 的长;⑶若将抛物线“2y x =”改为抛物线“2(0)y ax bx c a =++>”,其他条件不变,求CD 的长(用a 、b 、c 表示,并直接写出答案).25.已知抛物线2(1)y x m x m =+--经过点(-2,-3),并且与x 轴交于点A 、B 两点(点A 在点B 的左侧),交y 轴于点C . ⑴求抛物线的解析式;⑵设经过A 、B 两点的圆(AB 不是圆的直径)与AC 交于点E ,与直线3y x =+交于点F (点F 不在x 轴上),试判断△BEF 的形状,并说明理由(参看图图17 B AE F D P G C ABG C D E F P P F E D CG B A图18 图19图20 EPDC BA26.如图17,点G 、F 分别是等腰△ABC 、等腰△ADE 底边的中点,∠BAC =∠DAE =∠α,点P是线段CD 的中点.试探索:∠GPF 与∠α的关系,并加以证明.说明:⑴如果你反复探索,没有解决问题,请写出探索过程(要求至少写3步);⑵在你完成⑴之后,可以从如图18,如图19中选取一个图,完成解答(选取图18得10分;选取图19得5分).附加题:如图20,在26题中,若∠α=90°,连结BE ,试探索AP 与BE 的关系,并加以证明.2008年大连市初中毕业升学考试试测(二)数学参考答案与评分标准一、选择题1.D ;2.C ;3.C ; 4.A ;5.B ;6.B ; 7.A ;8.B . 二、填空题9.-2;10.2-≥x ;11.360º;12.a2;13.31 ;14. (―2,―3);15.1;16.正方形、矩形、菱形等.三、解答题17.解:设轮船在静水中的速度为x 千米/时, ······································ 1分根据题意,得.3334-=+x x ·························································· 6分 解得 x =21. ············································································· 7分 经检验x =21是原方程的解. ························································ 8分 答:轮船在静水中的速度为21千米/时. ··········································· 9分 18································································································ 4分 12x 2x 2+≥+. ········································································ 6分 证明:(x 2+2)—(2x+1)=x 2—2x+1 ················································ 7分 =(x —1)2≥0. ··········································································· 8分 ∴12x 2x 2+≥+. ····································································· 9分 19.解:在Rt △ABC 中,tan30º=ECBC. ··················································· 4分 ∴BC=ECtan30º, ··········································································· 5分 ∴BC=27tan30º, ············································································ 6分 ∴BD=BC+CD=1.5+27tan30º ······························································ 8分=3923+. ·············································································· 9分 答:旗杆的高BD 的长为(3923+)m . ·········································· 10分20.解:(1)10,10; ····································································· 4分(2)x 甲=)514233221101(101⨯+⨯+⨯+⨯+⨯+⨯ 2.7, ········ 6分 x 乙=)514132231102(101⨯+⨯+⨯+⨯+⨯+⨯ 2.2; ············· 8分 (3)甲班比乙班好一些;···················································· 10分 (4)甲班有一人,乙班有2人没有参加课外活动. ·················· 12分四、解答题21.解(1)直线的解析式为y=kx+b , ················································ 1分∵ 直线经过点(0,-2)和点(-2,0), ···························· 2分∴ ⎩⎨⎧=+--=.0b 2k ,2b ··································································· 4分解得⎩⎨⎧-=-=.2b ,1k ·········································································· 5分∴ 直线的解析式为y=2x --. ················································ 6分 (2)图(略). ········································································ 8分x <—3. ·········································································· 10分22. 解:(1)当x=a 时,y=a 2,∴A 点坐标为(a ,a2),∵AB ∥x 轴, ∴A 、B 两点纵坐标相等, ···················································· 1分a 2=x 1,∴x=2a . ······························································· 2分 ∴B 点坐标为(2a ,a2). ······················································· 3分 ∵AC ∥x 轴,∴A 、C 两点横坐标相等,∴x=a ,y=a1, ··················· 4分 ∴C 点坐标为(a ,a1). ···························································· 5分 (2)∵CD ∥x 轴,∴C 、D 两点纵坐标相等,a 1 =x2,∴x=2a . ∴D 点坐标为(2a , a1). ······················································ 6分 ∴AB=a -2a =2a , AC=a 2 -a 1=a1,CD=a , ···························· 8分 ∴S 四边形ABCD =21(2a +a )a1 ····················································· 9分 =43. ················································································· 10分 23.解:(1)对一个点得1分,对一个点得2分. ························ 2分△A``B``C``是所求作的三角形. ······ 3分 (2)∠BDB``=∠EDF .证明:连结DB 、DB`、DB``,∵△ABC 与△A`B`C`关于DE 对称, ∴∠BDE=∠B`DE , ····················· 4分又∵△A`B`C`与△A``B``C`直线DF 对称,∴∠B`DF=∠B``DF , ························· ··∠BDB``=∠B``DF+∠BDF ······················=∠B`DF+∠BDF ·······························=2∠BDE+∠BDF+∠BDF=2∠EDF . ·····五、解答题与附加题24.解:(1)∵AB=2,∴A 点的横坐标为-1,∴点A 纵坐标为1, ········· 1分∵点D 的纵坐标比点A 的纵坐标大1,∴点D 纵坐标为2, ·············· 2分∴2=x 2,∴x 1=2,x 2=-2. ·················································· 3分 B``∴CD的长为22. ································································· 4分(2)∵抛物线y=2x2-8x+9,∴抛物线的对称轴为直线x=2,∵AB=2,∴点A的横坐标为1,∴点A的纵坐标y=2-8+9=3,························· 5分∵点D的纵坐标比点A的纵坐标大1,∴点D纵坐标为4, ················· 6分∴4=2x2-8x+9,解得x1=264+,x2=264-. ······························· 7分CD=x1-x2=6. ····································································· 8分(3)2a 1a+或a aa22+. ·······················································10分25.解:(1)∵抛物线y=x2+(m-1)x-m经过点(-2,-3),∴-3=4-2(m-1)-m.··························· 1分解得m=3. ·············································· 2分∴抛物线的解析式为y=x2+2x-3. ················· 3分(2)△BEF为等腰直角三角形.当y=0时,x2+2x-3=0,解得x1=-3,x2=1.··· 4分当x=0时,y=-3.∴A、B、C三点坐标分别为(-3,0)、(1,0)、(0,-3). ············ 5分∴OA=OC,∠OAC=45º.··························································· 6分直线y=x+3与x轴、y轴的交点坐标分别为(-3,0)、(0,3),∴,∠FAO=45º.······································································ 7分∵∠BFE=∠OAC=45º,······························································ 8分∠BEF=∠FAO=45º, ································································· 9分∴∠EBF=90º,BE=BF,即△BEF为等腰直角三角形. ····················10分26.∠GPF=180º-∠α.··································································· 2分证明:连结BD,连结CE.∵AB=AC、AD=AE,∠BAC=∠DAE,··············································· 3分∴∠BAD=∠CAE, ········································································· 4分∴△ABD≌△ACE,········································································ 5分∴∠ABD=∠ACE. ········································································· 6分∵G、P、F分别是BC、CD、DE的中点, ··········································· 7分∴PG∥BD,PF∥CE. ····································································· 8分∴∠PGC=∠CBD, ········································································· 9分∠DPF=∠DCE=∠DCA+∠ACE=∠DCA+∠ABD, ································10分∠DPG=∠PGC+∠BCD=∠CBD+∠BCD , ··········································· 12分∠GPF=∠DPF+∠DPG=∠DCA+∠ABD+∠CBD+∠BCD=180º-∠BAC=180º-∠α, 13分 即∠GPF=180º-∠α. ······································································ 14分写探索过程要步步有据,写两步得1分,写三步得2分.选取图18证明:连结BD ,连结CE .∵AB=AC 、AD=AE ,∠BAC=∠DAE , ··············································· 3分∴∠BAD=∠CAE , ········································································· 4分∴△ABD ≌△ACE , ········································································ 5分∴∠ABD=∠ACE . ········································································· 6分设BD 与CE 交于点O ,AC 与BD 交于点K ,∠AKB=∠CKO ,∴∠BOC=∠BAC ,∠COD=180º-∠α. ·············································· 7分∵G 、P 、F 分别是BC 、CD 、DE 的中点,∴PG ∥BD ,PF ∥CE . ····································································· 8分∴∠GPC=∠BDC ,∠DPF=∠DCE , ··················································· 9分∠GPF=180º-∠GPC -∠DPF=180º-∠BDC -∠DCE=∠COD ,即∠GPF=180º-∠α. 10 选取图19证明:∵AB=AC 、AD=AE ,∴BD=CE , ······················································ 3分∵G 、P 、F 分别是BC 、CD 、DE 的中点,∴PG ∥BD ,PF ∥CE . ············· 4分∴∠ADC=∠DPG ,∠DPF=∠ACD ,∠GPF=∠DPF+∠DPG=∠ADC+∠ACD =180º-∠BAC=180º-∠α,即∠GPF=180º-∠α. ···························································· 5分附加题:AP=21BE ,AP ⊥BE . 证明:延长AP 至H ,使得PH=AP ,连结DH .∵P 是线段CD 的中点,∴DP=CP ,又∵PH=AP ,∠APC=∠HPD ,∴△APC ≌△HPD , ······························· 1分∴AC=DH ,∠H=∠CAP , ∴DH ∥AC ,∴∠ADH+∠DAC=180º,∠H=∠HAC . 2分∵AB=AC ,AD=AE ,∠ =90º,∴∠BAE=∠BAC+∠DAC -∠DAC=180º-∠DAC ,∴∠ADH=∠BAE , ········································································· 3分∴△ABE ≌△DHA ,∴BE=AH ,∠H=∠ABE ,∴AP=21BE , ·················· 4分 ∵∠α=90º,∴∠BAH+∠HAC=90º=∠BAH+∠H=∠BAH+∠ABE ,∴∠AFB=90º,即AP ⊥BE . ····························································· 5分。
2008年大连市初中毕业升学统一考1
2008年大连市初中毕业升学统一考试本试卷1~8页,五道大题,30道小题,满分100分。
考试时间100分钟,开卷考试。
一、选择题(本题20小题。
每小题1分。
共20分)说明:请将各题惟一正确答案的代号填入题后括号内。
1.罗瑞卿大将在参观虎门销烟遗址时说:“中国近代史就是在这儿首先开始了抵御帝国主义的侵略,到了虎门就能知道什么是中华民族精神。
”下列人物与此遗址有关的是( )A.林则徐B邓世昌G左宗棠n丁汝昌2.孙中山是中国民主革命伟大的先行者,1905年他建立的第一个全国规模的资产阶级革命政党是( )A.兴中会B.华兴会C.光复会n同盟会3.今年5月4日胡锦涛总书记参加了北京大学110周年校庆,他高度评价了北大对中国革命、建设和改革事业做出的重大贡献。
下列与北京大学有关的历史事件有( )①洋务运动②辛亥革命③新文化运动④五四运动A.①②R①④C.③④ D.②④4.中国人民解放军诞生至今已走过81个春秋,它诞生的标志性事件是( )A.武昌起义B.秋收起义C.井冈山会师D.南昌起义5.“五一”期间,小红去沈阳参观“九一八”纪念馆,看到一座残历碑式纪念建筑物(图1),它所反映的历史事件标志着中国( )B.全面抗战的开始C.全面内战的爆发D.红军长征的开始6.解放战争中,人民解放军以摧枯拉朽之势,推翻了国民党政权,取得了胜利。
人民解放战争迅速胜利的主要原因有( )①毛泽东等中央领导人的英明决策②解放军的英勇善战③人民群众的大力支持④先进的武器装备A.①②③B②③④C.①③④D.①②③④7.“一国两制”构想的提出得到了国内外人士的普遍赞誉。
英国前首相撒切尔夫人说:“一国两制’的构想是没有先例的天才创造,为香港特殊的历史环境提供了富有想象力的答案。
”提出这一伟大构想的是( )A.孙中山B毛泽东C.邓小平D.江泽民8.新中国成立后,我国在外交领域取得了巨大成就。
一FN成就按时间顺序排列正确的是( )①提出和平共处五项原则②美国总统尼克松访华,签署《中美联合公报》③中国在联合国的合法席位得到恢复④中美正式建立外交关系A.①②③④B.①③②④C.②①④③D.③①④②9.下列思想家、艺术家与他们的作品搭配不正确的一项是( )A.魏源——《海国图志》B.达·芬奇——《蒙娜丽莎》C.严复——《文学改良刍议》D.毕加索——《格尔尼卡》10.北京奥运会的口号是“One word One Dreanl.'(同一个世界同一个梦想)。
2008年中考数学试题及答案解析
C.通常情况下,抛出的篮球会下落
D.阴天就一定会下雨
A.
5.一次函数 y kx b 的图象如图所示,当 y 0 时, x 的取
值范围是(
A. x 0
)
B. x 0
C. 253104 亩
B.
C. (2,1) D. (1,2)
C. x 2
6.若等腰三角形中有一个角等于 50 ,则这个等腰三角形的顶角的度数为( )
22.小刚和小明两位同学玩一种游戏.游戏规则为:两人各执“象、虎、鼠”三张牌,同 时各出一张牌定胜负,其中象胜虎、虎胜鼠、鼠胜象,若两人所出牌相同,则为平局.例 如,小刚出象牌,小明出虎牌,则小刚胜;又如,两人同时出象牌,则两人平局. (1)一次出牌小刚出“象”牌的概率是多少?
(2)如果用 A,, B C 分别表示小刚的象、虎、鼠三张牌,用 A1 , B1 , C1 分别表示小明
10.分解因式: 2m3 8m
11.已知 △ABC 中, A 60 , ABC , ACB 的平分线交于点 O ,
则 BOC 的度数为
.
12.如图所示,菱形 ABCD 中,对角线 AC,BD 相交于点 O ,若再补 B
充一个条件能使菱形 ABCD 成为正方形,则这个条件是
填一个条件即可).
的象、虎、鼠三张牌,那么一次出牌小刚胜小明的概率是多少?用列表法或画树状图(树
形图)法加以说明.
小刚
ABC
对全部高中资料试卷电气设备,在安装过程中以及安装结束后进行高中资料试卷调整试验;通电检查所有设备高中资料电试力卷保相护互装作置用调与试相技互术关,系电,力根通保据过护生管高产线中工敷资艺设料高技试中术卷资0配不料置仅试技可卷术以要是解求指决,机吊对组顶电在层气进配设行置备继不进电规行保范空护高载高中与中资带资料负料试荷试卷下卷问高总题中体2资2配,料置而试时且卷,可调需保控要障试在各验最类;大管对限路设度习备内题进来到行确位调保。整机在使组管其高路在中敷正资设常料过工试程况卷中下安,与全要过,加度并强工且看作尽护下可关都能于可地管以缩路正小高常故中工障资作高料;中试对资卷于料连继试接电卷管保破口护坏处进范理行围高整,中核或资对者料定对试值某卷,些弯审异扁核常度与高固校中定对资盒图料位纸试置,卷.编保工写护况复层进杂防行设腐自备跨动与接处装地理置线,高弯尤中曲其资半要料径避试标免卷高错调等误试,高方要中案求资,技料编术试写5交、卷重底电保要。气护设管设装备线备置4高敷、调动中设电试作资技气高,料术课中并3试中、件资且卷包管中料拒试含路调试绝验线敷试卷动方槽设技作案、技术,以管术来及架避系等免统多不启项必动方要方式高案,中;为资对解料整决试套高卷启中突动语然过文停程电机中气。高课因中件此资中,料管电试壁力卷薄高电、中气接资设口料备不试进严卷行等保调问护试题装工,置作合调并理试且利技进用术行管,过线要关敷求运设电行技力高术保中。护资线装料缆置试敷做卷设到技原准术则确指:灵导在活。分。对线对于盒于调处差试,动过当保程不护中同装高电置中压高资回中料路资试交料卷叉试技时卷术,调问应试题采技,用术作金是为属指调隔发试板电人进机员行一,隔变需开压要处器在理组事;在前同发掌一生握线内图槽部纸内故资,障料强时、电,设回需备路要制须进造同行厂时外家切部出断电具习源高题高中电中资源资料,料试线试卷缆卷试敷切验设除报完从告毕而与,采相要用关进高技行中术检资资查料料和试,检卷并测主且处要了理保解。护现装场置设。备高中资料试卷布置情况与有关高中资料试卷电气系统接线等情况,然后根据规范与规程规定,制定设备调试高中资料试卷方案。
2008年辽宁省十二市初中毕业升学统一考试、数学试卷
2008年辽宁省十二市初中毕业生学业考试数学试卷(六三制)*考试时间120分钟 试卷满分150分一、选择题(下列各题的备选答案中,只有一个是正确的,请将正确答案的序号填入下面表格内,每小题3分,共1.截止2008年6月7日12时,全国各地支援四川地震灾区的临时安置房已经安装了40600套.这个数用科学记数法表示为( ) A .50.40610⨯套 B .44.0610⨯套C .340.610⨯套D .240610⨯套2.如图1,直线12l l ∥,l 分别与12l l ,相交,如果2120∠=, 那么1∠的度数是( ) A .30B .45C .60D .753.下列事件中是必然事件的是( ) A .阴天一定下雨B .随机掷一枚质地均匀的硬币,正面朝上C .男生的身高一定比女生高D .将油滴在水中,油会浮在水面上4.图2是由几个相同的小正方体搭成的一个几何体,它的俯视图是( )5.下列命题中正确的是( )A .两条对角线互相平分的四边形是平行四边形B .两条对角线相等的四边形是矩形C .两条对角线互相垂直的四边形是菱形D .两条对角线互相垂直且平分的四边形是正方形 6.若反比例函数(0)ky kx=≠的图象经过点(21)-,,则这个函数的图象一定经过点( ) A .122⎛⎫- ⎪⎝⎭,B .(12),C .112⎛⎫- ⎪⎝⎭,D .(12)-, 7.不等式组2133x x +⎧⎨>-⎩≤的解集在数轴上表示正确的是( )A .B .C .D .图2A .B .C .D .l l 1 l 212图18.图3是对称中心为点O 的正八边形.如果用一个含45角的直角三角板的角,借助点O (使角的顶点落在点O 处)把这个正八边形的面积n 等分. 那么n 的所有可能的值有( ) A .2个 B .3个 C .4个 D .5个 二、填空题(每小题3分,共24分) 9.分解因式:34x y xy -= .10.体育老师对甲、乙两名同学分别进行了8次跳高测试,经计算这两名同学成绩的平均数相同,甲同学的方差是2 6.4S =甲,乙同学的方差是28.2S =乙,那么这两名同学跳高成绩比较稳定的是 同学.11.一元二次方程2210x x -+=的解是 .12.如图4,D E ,分别是ABC △的边A B A C,上的点,DE BC ∥,2ADDB=,则:AD EA B C S S =△△.13.如图5,假设可以在图中每个小正方形内任意取点(每个小正方形除颜色外完全相同),那么这个点取在阴影部分的概率是 .14.一个圆锥底面周长为4πcm ,母线长为5cm ,则这个圆锥的侧面积是 .15.如图6,观察下列图案,它们都是由边长为1cm 的小正方形按一定规律拼接而成的,依此规律,则第16个图案中的小正方形有 个.图616.如图7,直线3y x =+与x 轴、y 轴分别相交于A B , 两点,圆心P 的坐标为(10),,P 与y 轴相切于点O .若将P沿x 轴向左移动,当P 与该直线相交时,横坐标为整数的点P有 个. 三、(每小题8分,共16分)17.先化简,再求值:23111aa a a a a-⎛⎫- ⎪-+⎝⎭,其中2a =.图5图案1图案2图案3图案4……AE CD B图4图318.如图8所示,在网格中建立了平面直角坐标系,每个小正方形的边长均为1个单位长度,将四边形ABCD 绕坐标原点O 按顺时针方向旋转180后得到四边形1111A B C D .(1)直接写出1D 点的坐标;(2)将四边形1111A B C D 平移,得到四边形2222A B C D ,若2(45)D ,,画出平移后的图形.(友情提示:画图时请不要涂错阴影的位置哦!)四、(每小题10分,共20分)19.如图9,有四张背面相同的纸牌A B C D ,,,,其正面分别画有四个不同的图形,小明将这四张纸牌背面朝上洗匀后随机摸出一张,放回后洗匀再随机摸出一张.(1)用树状图(或列表法)表示两次摸牌所有可能出现的结果(纸牌用A B C D ,,,表示); (2)求两次摸牌的牌面图形既是中心对称图形又是轴对称图形的概率.20.如图10,AB 为O 的直径,D 为弦BE 的中点,连接OD 并延长交O 于点F ,与过B 点的切线相交于点C .若点E 为AF 的中点,连接AE . 求证:ABE OCB △≌△.图8图9图10ODB CF EA五、(每小题10分,共20分)21.某中学开展以“我最喜欢的职业”为主题的调查活动.通过对学生的随机抽样调查得到一组数据,下面两图(如图11、图12)是根据这组数据绘制的两幅不完整的统计图.请你根据图中所提供的信息解答下列问题:(1)求在这次活动中一共调查了多少名学生?(2)在扇形统计图中,求“教师”所在扇形的圆心角的度数. (3)补全两幅统计图.22.在“汶川地震”捐款活动中,某同学对甲、乙两班捐款情况进行了统计:甲班捐款人数比乙班捐款人数多3人,甲班共捐款2400元,乙班共捐款1800元,乙班平均每人捐款的钱数是甲班平均每人捐款钱数的45倍.求甲、乙两班各有多少人捐款? 六、(每小题10分,共20分)23.如图13,某数学兴趣小组在活动课上测量学校旗杆高度.已知小明的眼睛与地面的距离()AB 是1.7m ,看旗杆顶部M 的仰角为45;小红的眼睛与地面的距离()CD 是1.5m ,看旗杆顶部M 的仰角为30.两人相距28米且位于旗杆两侧(点B N D ,,在同一条直线上).请求出旗杆MN 的高度.1.41.7,结果保留整数)其它 教师 医生公务员 军人10% 20%15% 图11 图12 MN BA DC30° 45°图1324.2008年6月1日起,我国实施“限塑令”,开始有偿使用环保购物袋.为了满足市场需求,某厂家生产A B ,两种款式的布质环保购物袋,每天共生产4500个,两种购物袋的成本和售价如下表,设每天生产A 种购物袋x 个,每天共获利y 元.(1)求出y 与x (2)如果该厂每天最多投入成本10000元,那么每天最多获利多少元? 七、(本题12分)25.如图14,在Rt ABC △中,90A ∠=,AB AC =,BC =另有一等腰梯形DEFG (GF DE ∥)的底边DE 与BC 重合,两腰分别落在AB AC ,上,且G F ,分别是AB AC ,的中点. (1)求等腰梯形DEFG 的面积;(2)操作:固定ABC △,将等腰梯形DEFG 以每秒1个单位的速度沿BC 方向向右运动,直到点D 与点C重合时停止.设运动时间为x 秒,运动后的等腰梯形为DEF G ''(如图15).探究1:在运动过程中,四边形BDG G '能否是菱形?若能,请求出此时x 的值;若不能,请说明理由.探究2:设在运动过程中ABC △与等腰梯形DEFG 重叠部分的面积为y ,求y 与x 的函数关系式.八、(本题14分)26.如图16,在平面直角坐标系中,直线y =-与x 轴交于点A ,与y 轴交于点C ,抛物线A F G (D )BC (E ) 图14F G A F ' G ' B D CE 图152(0)y ax c a =+≠经过A B C ,,三点. (1)求过A B C ,,三点抛物线的解析式并求出顶点F 的坐标;(2)在抛物线上是否存在点P ,使ABP △为直角三角形,若存在,直接写出P 点坐标;若不存在,请说明理由;(3)试探究在直线AC 上是否存在一点M ,使得MBF △的周长最小,若存在,求出M 点的坐标;若不存在,请说明理由.2008年辽宁省十二市初中毕业生学业考试数学试卷(六三制)答案一、选择题(每小题3分,共24分)二、填空题(每小题3分,共24分) 9.(2)(2)xy x x +-10.甲11.121x x ==12.4:913.72514.210cm π(丢单位扣1分) 15.13616.3三、(每小题8分,共16分)17.解法一:原式223(1)(1)11a a a a a a a+---=⨯- ·················································· 2分24a =+ ······································································································ 6分 当2a =时,原式2248=⨯+= ········································································ 8分解法二:原式3(1)(1)(1)(1)11a a a a a a a a a a +-+-=⨯-⨯-+ ····································· 2分 24a =+ ······································································································ 6分 当2a =时,原式2248=⨯+= ········································································ 8分 18.解:(1)1(31)D -, ····························································································· 2分(2)2A ,222B C D ,,描对一个点给1分. ······················································· 6分 画出正确图形(见图1) ·················································································· 8分x四、(每小题10分,共20分) 19.(1··········································· 6分(2)从表中可以得到,两次摸牌所有可能出现的结果共有16种,其中既是中心对称图形又是轴对称图形的有9种. ··································································································· 8分 故所求概率是916.························································································ 10分 19.(1)解法二:所以可能出现的结果:(A ,A ),(A ,B ),(A ,C ),(A ,D ),(B ,A ),(B ,B ),(B ,C ),(B ,D ),(C ,A ),(C ,B ),(C ,C ),(C ,D ),(D ,A ),(D ,B ),(D ,C ),(D ,D ). ······································································ 6分 (2)以下同解法1. 20.解:(1)证明:如图2. AB 是O 的直径.90E ∴∠= ······························································· 1分又BC 是O 的切线,90OBC ∴∠=A B C DA ABC DB A BC DC A B C DD 开始第一次牌面的字母第二次牌面的字母 图1图2OD BC F EAE OBC ∴∠=∠ ························································· 3分 OD 过圆心,BD DE =,EF FB ∴=BOC A ∴∠=∠. ·························································································· 6分 E 为AF 中点,EF BF AE ∴==30ABE ∴∠= ······························································································ 8分 90E ∠=12AE AB OB ∴== ······················································································· 9分 ABE OCB ∴△≌△. ··················································································· 10分 五、(每小题10分,共20分)21.(1)被调查的学生数为4020020=%(人) ························································· 2分 (2)“教师”所在扇形的圆心角的度数为70115201010036072200⎛⎫----⨯⨯= ⎪⎝⎭%%%% ·············································· 5分 (3)如图3,补全图 ······················································································ 8分如图4,补全图 ····························································································· 10分22.解法一:设乙班有x 人捐款,则甲班有(3)x +人捐款. ··································· 1分 根据题意得:24004180035x x⨯=+ ·························································································· 5分 解这个方程得45x =. ··················································································· 8分 经检验45x =是所列方程的根. ······································································· 9分 348x ∴+=(人)答:甲班有48人捐款,乙班有45人捐款. ························································ 10分 解法二:设甲班有x 人捐款,则乙班有(3)x -人捐款. ········································· 1分 根据题意得:其它 教师医生 公务员军人10% 20%15%图3图435%20%24004180053x x ⨯=- ·························································································· 5分 解这个方程得48x =. ··················································································· 8分 经检验48x =是所列方程的根. ······································································· 9分 345x ∴-=(人)答:甲班有48人捐款,乙班有45人捐款. ························································ 10分 六、(每小题10分,共20分) 23.解法一:解:过点A 作AE MN ⊥于E ,过点C 作CF MN ⊥于F , ································· 1分 则 1.7 1.50.2EF AB CD =-=-=···································································· 2分 在Rt AEM △中,90AEM ∠=,45MAE ∠=AE ME ∴= ································································································· 3分 设AE ME x ==(不设参数也可) 0.2MF x ∴=+,28FC x =- · (5)分 在Rt MFC △中,90MFC ∠=,30MCF ∠=tan MF CF MCF ∴=∠0.2)3x x ∴+=- ········································· 7分10.0x ∴≈12MN ∴≈ ································································································· 9分 答:旗杆高约为12米. ·················································································· 10分解法二:解:过点A 作AE MN ⊥于E ,过点C 作CF MN ⊥于F , ····················· 1分 则 1.7 1.50.2EF AB CD =-=-=···································································· 2分 在Rt AEM △中,90AEM ∠=,45MAE ∠=AE ME ∴=设AE x =,则0.2MF x =+ ··········································································· 3分在Rt MFC △中,90MFC ∠=,30MCF ∠=tan 603(0.2)CF MF x ==+ ······································································ 5分BN ND BD +=0.2)28x x ∴+= ··················································································· 7分解得10.2x ≈12MN ∴≈ ································································································· 9分 答:旗杆高约为12米. ·················································································· 10分 (注:其他方法参照给分) 24.解:(1)根据题意得:(2.32)(3.53)(4500)0.22250y x x x =-+--=-+ ··················· 2分 (2)根据题意得:23(4500)10000x x +-≤ ····················································· 5分MN BA DC30° 45°图5EF解得3500x ≥元 ··························································································· 6分 0.20k =-<,y ∴随x 增大而减小 ································································ 8分 ∴当3500x =时0.2350022501550y =-⨯+= ········································································ 9分 答:该厂每天至多获利1550元.······································································ 10分 七、(本题12分) 25.解:如图6,(1)过点G 作GM BC ⊥于M .AB AC =,90BAC ∠=,BC =G 为AB 中点GM ∴= ········································· 1分又G F ,分别为AB AC ,的中点12GF BC ∴==······························· 2分162DEFG S ∴==梯形 ∴等腰梯形DEFG 的面积为6. ······································································· 3分(2)能为菱形 ······························································································· 4分如图7,由BG DG '∥,GG BC '∥∴四边形BDG G '是平行四边形 ··················· 6分当122BD BG AB ===时,四边形BDG G '为菱形,此时可求得2x =∴当2x =秒时,四边形BDG G '为菱形. ····· 8分(3)分两种情况:①当0x <≤方法一:GM =BDG GS'∴=∴重叠部分的面积为:6y =∴当0x <≤y 与x的函数关系式为6y = ··································· 10分方法二:当0x <≤FG x '=,DC x =,GM =∴重叠部分的面积为:6y ==-∴当0x <≤y 与x的函数关系式为6y = ··································· 10分AFG (D )B C (E ) 图6M F G A F 'G ' BD CE图7M。
大连市2008年高级中等学校招生考试化学
辽宁省大连市2008年初中毕业升学统一考试化学(满分100分,考试时间100分钟)可能用到的相对原子质量:H—1 C—12 N—14 O—16 Na—23 Cl—35.5 K—39 Mn—55 Ag—108 一、选择题(本题共18小题,每小题1分,共18分,说明:每小题只有一个选项符合题意)1.下列变化中,属于物理变化的是()A.酸雨形成B.冰雪融化C.甲烷燃烧D.食物腐烂2.空气中含量最多且化学性质不活泼的气体是()A.氮气B.氧气C.稀有气体D.二氧化碳3.下列物质中,属于氧化物的是()A.O2B.C6H12O6C.H2O D.K2CO34.日常生活中,降低天然水硬度的简单方法是()A.过滤B.吸附C.消毒D.煮沸5.下列化工产品中,属于石油加工产品的是()A.煤气B.柴油C.煤焦油D.焦炉气6.下列做法不会危害人体健康的是()A.将霉变的大米洗净后做饭B.为低血糖病人补充葡萄糖C.用甲醛溶液浸泡海产品D.误用亚硝酸钠烹饪食物7.碳酸氢铵(NH4HCO3)是一种常用的化肥,它属于()A.氮肥B.磷肥C.钾肥D.复合肥料8.下列实验操作正确的是()9.人体缺少必需微量元素易得病。
因摄入量不足引起贫血的微量元素是()A.锌B.铁C.硒D.碘10.下列物质的化学式书写正确的是()A.氧化铝AlO B.氦气He2C.氯化亚铁FeCl3D.氢氧化钾KOH11.下列物品中,由有机合成材料制成的是()A.铝制易拉罐B.瓷碗C.玻璃杯D.塑料瓶12.某粒子的结构示意图为,该粒子属于()A.原子B.阳离子C.阴离子D.分子13.下列做法中,利用乳化的原理达到清洗目的的是()A.用自来水清洗蔬菜B.用汽油清洗油污C.用洗涤剂清洗餐具D.用酒精清洗碘渍14.通过电解水实验,得出的结论正确的是()A.水由氢、氧两种元素组成B.水由氢气和氧气组成C.水由氢分子和氧原子构成D.水由两个氢原子和一个氧原子构成15.钛和钛合金被认为是21世纪的重要金属材料。
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B A 2008年辽宁省大连市初中毕业中考数学升学统一考试试题
本试卷1~8页,共150分,考试时间120分钟。
一、选择题(本题8小题,每小题3分,共24分)
说明:将下列各题唯一正确的答案代号A 、B 、C 、D 填到题后的括号内。
1.在平面直角坐标系中,点P (2,3)在 ( )
A .第一象限
B .第二象限
C .第三象限
D .第四象限 2.下列运算中,结果正确的是 ( )
A .3412a a a ⋅=
B .10
25
a
a a ÷=
C .2
3
5
a a a += D .43a a a -=
3.2007年8月对列车服务情况进行了调查,
其中不满意情况的百分比如图1,由图中的数据可知,列车服务最需要 改进的方面是 ( )
A .列车员态度
B .超载
C . 车厢卫生
D .物价太贵
4.如图,两温度计读数分别为我国某地今年2月份某天的最 低气温与最高气温,那么这天的最高气温比最低气温高( ) A .5°C B .7°C C .12°C D .-12°C
5.在共有15人参加的的“我爱祖国”演讲比赛中,参赛选手要想知道自己是否能进入前8名,只需要了解自己的成绩以及全部成绩的 ( )
A .中位数
B .众数
C .平均数
D .方差
6.下列图形中,恰好能与图3拼成一个矩形的是 ( )
D
C B A 图 3
7.若运算程序为:输出的数比该数的平方小1.则输入 ( ) A .10 B .11 C .12 D .13
8.如图,梯形ABCD 中,AD ∥BC ,中位线EF 交BD 于点O , 若FO -EO = 5,则BC -AD 为( ) 二、填空题(本题共8小题,每小题3分,共24分)
F E
D
C
B
A O
C
B
说明:将答案直接填在题后的横线上。
9.若两圆的半径分别为5和2,圆心距为7,则这两个圆的位置关系是__________. 10.小明和小红练习射击,第一轮10枪打完后两人的成绩如图5, 一般新手的成绩不太稳定,小明和小红二人有一人是新手,估计 小明和小红两人中新手是______________.
11.关于x 的某个不等式组的解集在数轴上表示为如图6,则不等式
组的解集为_________________________.
12.如图,锐角三角形ABC 的边AB 和AC 上的高线CE 和BF 相交于点D . 请写出图中的一对相似三角形______________________.
13.△ABC 平移到△DEF ,若AD = 5,则CF 为_____________. 14.反比例函数k y x
=
的图象经过点(2,3),则这个反比例函数
的解析式为_______________.
15.如图,画出△OAB 绕O 点按逆时针方向旋转90°时 的△OA
′B ′. 16
.若12
x =
,12y =
,则x + y 的
值为______________.
三、解答题(本题共4小题,其中17、18题各9分, 19题10分,20题各12分,共40分) 17.化简:2
2
2
93169
3
a
a a a a a a
--÷
+
+++
18.如图,一块长方形铁皮的长是宽的2倍,四个角各截去一个正方形,制成高是5cm,容积是500cm3的无盖长方体容器,求这块铁皮的长和宽.
19.如图,P A、PB是⊙O的切线,切点分别为A、B、C是⊙O上一点,若∠APB = 40°,求∠ACB的度数.
20.某活动小组为了估计装有5个白球和若干个红球(每个球除颜色外都相同)的袋中红球接近多少个,在不将袋中球倒出来的情况下,分小组进行摸球试验,两人一组,共20组进行摸球实验.其中一位学生摸球,另一位学生记录所摸球的颜色,并将球放回袋中摇匀,每一组做400次试验,汇兑起来后,摸到红球次数为6000次.
⑴估计从袋中任意摸出一个球,恰好是红球的概率是多少?
⑵请你估计袋中红球接近多少个?
四、解答题(本题共3小题,其中2121.已知二次函数2y ax bx =+的图象经过点(2,0)、(-1⑴求二次函数的解析式;
⑵不用列表,在下图中画出函数图象,观察图象写出y > 0x 的取值范围.
22.为了测得学校旗杆的高度,小明先站在地面的A 点测得旗杆最高点C 的仰角为27°(点A 距旗杆的距离大于50m),然后他向旗杆的方向向前进了50m ,此时测得点C 的仰角为40度.又已知小明的眼睛离地面 1.6m ,请你画出小明测量的示意图,并帮小明计算学校旗杆的高度.(精确到0.1m).
23.某仓库甲、乙、丙三辆运货车,每辆车只负责进货或出货,每小时的运输量丙车最多,乙四最少,乙车的运输量为每小时6吨,下图是从早晨上班开始库存量y (吨)与时间x (小时)的函数图象,OA段只有甲、丙车工作,AB段只有乙、丙车工作,BC段只有甲、乙工作.
⑴从早晨上班开始,库存每增加2吨,需要几小时?
⑵问甲、乙、丙三辆车,谁是进货车,谁是出货车?
⑶若甲、乙、丙三车一起工作,一天工作8小时,仓库的库存量有什么变化?
图24-1
五、解答题和附加题(本题共3小题,24题 10分,25题14分,26题附加题5分,全卷累积不超过150分,建议考生最后答附加题)
24.如图24-1,抛物线2
y x =的顶点为P ,A 、B 是抛物线上两点,AB ∥x 轴,四边形ABCD 为矩形,CD 边经过点P ,AB = 2AD . ⑴求矩形ABCD 的面积;
⑵如图24-2,若将抛物线“2
y x =”,改为抛物线“2
y x bx c =++”,其他条件不变,请猜想矩形ABCD 的面积;
⑶若将抛物线“2
y x bx c =++”改为抛物线“2
y ax bx c =++”,其他条件不变,请猜想矩形ABCD 的面积(用a 、b 、c 表示,并直接写出答案).
附加题:若将24题中“2
y x =”改为“2
y ax bx c =++”,“AB = 2AD ”条件不要,其他条件不变,探索矩形ABCD 面积为常数时,矩形ABCD 由.
25.如图25-1,正方形ABCD 和正方形QMNP ,∠M =∠B ,M 是正方形ABCD 的对称中心,MN 交AB 于F ,QM 交AD 于E . ⑴求证:ME = MF .
⑵如图25-2,若将原题中的“正方形”改为“菱形”,其他条件不变,探索线段ME 与线段MF 的关系,并加以证明.
⑶如图25-3,若将原题中的“正方形”改为“矩形”,且AB = m BC ,其他条件不变,探索线段ME 与线段MF 的关系,并说明理由.
⑷根据前面的探索和图25-4,你能否将本题推广到一般的平行四边形情况?若能,写出推广命题;若不能,请说明理由.
图25 - 4
图25 - 3
图25 - 2
图25 -1
N
G
F
E C
B A
D
26.如图,△ABC 的高AD 为3,BC 为4,直线EF ∥BC ,交线段AB 于E ,交线段AC 于F ,交AD 于G ,以EF 为斜边作等腰直角三角形PEF (点P 与点A 在直线EF 的异侧),设EF 为x ,△PEF 与四边形BCEF 重合部分的面积为y .
⑴求线段AG (用x 表示);
⑵求y 与x 的函数关系式,并求x 的取值范围.。