江苏省无锡市大桥实验中学2020-2021学年度九年级上册9AU1单元练习卷
2020-2021无锡市大桥中学九年级数学上期中试卷含答案
2020-2021无锡市大桥中学九年级数学上期中试卷含答案一、选择题1．函数y ＝﹣x 2﹣4x ﹣3图象顶点坐标是（ ）A ．（2，﹣1）B ．（﹣2，1）C ．（﹣2，﹣1）D ．（2，1） 2．二次函数y ＝ax 2+bx+c （a≠0）的图象如图所示，那么下列说法正确的是（ ）A ．a ＞0，b ＞0，c ＞0B ．a ＜0，b ＞0，c ＞0C ．a ＜0，b ＞0，c ＜0D ．a ＜0，b ＜0，c ＞03．已知抛物线y=x 2-2mx-4（m ＞0）的顶点M 关于坐标原点O 的对称点为M′，若点M′在这条抛物线上，则点M 的坐标为（ ）A ．（1，-5）B ．（3，-13）C ．（2，-8）D ．（4，-20）4．如图所示的暗礁区，两灯塔A ，B 之间的距离恰好等于圆的半径，为了使航船（S ）不进入暗礁区，那么S 对两灯塔A ，B 的视角∠ASB 必须（ ）A ．大于60°B ．小于60°C ．大于30°D ．小于30° 5．已知()222226x y y x +-=+，则22x y +的值是（ ） A ．－2B ．3C ．－2或3D ．－2且3 6．在平面直角坐标系中，点A （m ，2）与点B （3，n ）关于y 轴对称，则（ ） A ．m ＝3，n ＝2 B ．m ＝﹣3，n ＝2C ．m ＝2，n ＝3D ．m ＝﹣2，n ＝﹣3 7．若关于x 的方程240kx x -+=有实数根，则k 的取值范围是( )A ．k 16≤B ．1k 16≤C ．k 16≤且k 0≠D ．1k 16≤且k 0≠ 8．若关于x 的一元二次方程ax 2+bx ﹣1＝0（a ≠0）有一根为x ＝2019，则一元二次方程a （x ﹣1）2+b （x ﹣1）＝1必有一根为（ ）A ．12019B ．2020C ．2019D ．20189．将函数y=kx 2与y=kx+k 的图象画在同一个直角坐标系中，可能的是（ ）A．B．C．D．10．用1、2、3三个数字组成一个三位数，则组成的数是偶数的概率是（）A．13B．14C．15D．1611．在方格纸中，选择标有序号①②③④中的一个小正方形涂黑，与图中涂色部分构成中心对称图形．该小正方形的序号是（）A．①B．②C．③D．④12．如图，在⊙O中，AB是⊙O的直径，AB＝10，»»»AC CD DB==，点E是点D关于AB的对称点，M是AB上的一动点，下列结论：①∠BOE＝60°；②∠CED＝12∠DOB；③DM⊥CE；④CM＋DM的最小值是10，上述结论中正确的个数是()A．1B．2C．3D．4二、填空题13．已知、是方程的两个根，则代数式的值为______.14．已知方程x2﹣3x+k=0有两个相等的实数根，则k=_____．15．新园小区计划在一块长为20米，宽12米的矩形场地上修建三条互相垂直的长方形甬路（一条橫向、两条纵向，且横向、纵向的宽度比为3：2），其余部分种花草．若要使种花草的面积达到144米2．则横向的甬路宽为_____米．16．如图，五边形ABCD内接于⊙O，若AC=AD，∠B+∠E=230°，则∠ACD的度数是__________．17．要为一幅矩形照片配一个镜框，如图，要求镜框的四条边宽度都相等，且镜框所占面积是照片本身面积的四分之一，已知照片的长为21cm，宽为10cm，求镜框的宽度．设镜框的宽度为xcm，依题意列方程，化成一般式为_____．18．在阳光中学举行的春季运动会上，小亮和大刚报名参加100米比赛，预赛分A B C D四组进行，运动员通过抽签来确定要参加的预赛小组，小亮和大刚恰好抽到同,,,一个组的概率是_______．19．用半径为12cm，圆心角为90°的扇形纸片围成一个圆锥的侧面（接缝忽略不计），则该圆锥底面圆的半径为_______cm．20．如图，在扇形AOB中，∠AOB=90°，点C为OA的中点，CE⊥OA交»AB于点E，以点O为圆心，OC的长为半径作»CD交OB于点D，若OA=2，则阴影部分的面积为 .三、解答题21．“a2≥0”这个结论在数学中非常有用，有时我们需要将代数式配成完全平方式．例如：x2+4x+5＝x2+4x+4+1＝（x+2）2+1，∵（x+2）2≥0，∴（x+2）2+1≥1，∴x2+4x+5≥1．试利用“配方法”解决下列问题：（1）填空：x2﹣4x+5＝（x）2+；（2）已知x2﹣4x+y2+2y+5＝0，求x+y的值；（3）比较代数式：x2﹣1与2x﹣3的大小．22．已知：如图，AB是⊙O的弦，⊙O的半径为10，OE、OF分别交AB于点E、F，OF 的延长线交⊙O于点D，且AE=BF，∠EOF=60°．（1）求证：△OEF是等边三角形；（2）当AE=OE时，求阴影部分的面积．（结果保留根号和π）23．工人师傅用一块长为10dm，宽为6dm的矩形铁皮制作一个无盖的长方体容器，需要将四角各裁掉一个正方形．（厚度不计）（1）在图中画出裁剪示意图，用实线表示裁剪线，虚线表示折痕；并求长方体底面面积为12dm2时，裁掉的正方形边长多大？（2）若要求制作的长方体的底面长不大于底面宽的五倍，并将容器进行防锈处理，侧面每平方分米的费用为0.5元，底面每平方分米的费用为2元，裁掉的正方形边长多大时，总费用最低，最低为多少？24．三辆汽车经过某收费站下高速时，在2个收费通道A，B中，可随机选择其中的一个通过．（1）三辆汽车经过此收费站时，都选择A通道通过的概率是；（2）求三辆汽车经过此收费站时，至少有两辆汽车选择B通道通过的概率．25．如图，在中，，是的外接圆，点P在直径BD的延长线上，且．求证：PA是的切线；若，求图中阴影部分的面积结果保留和根号【参考答案】***试卷处理标记，请不要删除一、选择题1．B解析：B【解析】【分析】将函数解析式化为顶点式，即可得到顶点坐标.【详解】解：∵y ＝﹣x 2﹣4x ﹣3＝﹣（x 2+4x+4﹣4+3）＝﹣（x+2）2+1 ∴顶点坐标为（﹣2，1）；故选：B ．【点睛】本题考查了二次函数，解题关键是能将一般式化为顶点式.2．B解析：B【解析】【分析】利用抛物线开口方向确定a 的符号，利用对称轴方程可确定b 的符号，利用抛物线与y 轴的交点位置可确定c 的符号．【详解】∵抛物线开口向下，∴a ＜0，∵抛物线的对称轴在y 轴的右侧，∴x ＝﹣2b a＞0， ∴b ＞0， ∵抛物线与y 轴的交点在x 轴上方，∴c ＞0，故选：B ．【点睛】本题考查了二次函数图象与系数的关系：对于二次函数y ＝ax 2+bx +c （a ≠0），二次项系数a 决定抛物线的开口方向和大小：当a ＞0时，抛物线向上开口；当a ＜0时，抛物线向下开口；一次项系数b 和二次项系数a 共同决定对称轴的位置：当a 与b 同号时（即ab ＞0），对称轴在y 轴左； 当a 与b 异号时（即ab ＜0），对称轴在y 轴右；常数项c 决定抛物线与y 轴交点位置：抛物线与y 轴交于（0，c ）；抛物线与x 轴交点个数由△决定：△＝b 2﹣4ac ＞0时，抛物线与x 轴有2个交点；△＝b 2﹣4ac ＝0时，抛物线与x 轴有1个交点；△＝b 2﹣4ac ＜0时，抛物线与x 轴没有交点．3．C解析：C【解析】【分析】【详解】解：22224=()4y x mx x m m =-----，∴点M （m ，﹣m 2﹣4），∴点M′（﹣m ，m 2+4），∴m 2+2m 2﹣4=m 2+4．解得m=±2．∵m ＞0，∴m=2，∴M （2，﹣8）． 故选C ．【点睛】本题考查二次函数的性质． 4．D解析：D【解析】试题解析：连接OA ，OB ，AB ，BC ，如图：∵AB=OA=OB ，即△AOB 为等边三角形，∴∠AOB=60°，∵∠ACB 与∠AOB 所对的弧都为»AB ，∴∠ACB=12∠AOB=30°， 又∠ACB 为△SCB 的外角， ∴∠ACB ＞∠ASB ，即∠ASB ＜30°．故选D5．B解析：B【解析】试题分析：根据题意，先移项得()2222260x y y x +---=，即()2222260x y x y （）+-+-=，然后根据“十字相乘法”可得2222(2)(3)0x y x y +++-= ，由此解得22x y +=-2（舍去）或223x y +=.故选B.点睛：此题主要考查了高次方程的解法，解题的关键是把其中的一部分看做一个整体，构造出简单的一元二次方程求解即可.6．B解析：B【解析】【分析】根据“关于y 轴对称的点，横坐标互为相反数，纵坐标相同”解答．【详解】∵点A （m ，2）与点B （3，n ）关于y 轴对称，∴m ＝﹣3，n ＝2．故选：B ．【点睛】本题考查了关于x 轴、y 轴对称的点的坐标，解决本题的关键是掌握好对称点的坐标规律：（1）关于x 轴对称的点，横坐标相同，纵坐标互为相反数；（2）关于y 轴对称的点，纵坐标相同，横坐标互为相反数；（3）关于原点对称的点，横坐标与纵坐标都互为相反数．7．B解析：B【解析】【分析】当0k =时，代入方程验证即可，当0k ≠时，根据方程的判别式△≥0可得关于k 的不等式，解不等式即得k 的取值范围，问题即得解决.【详解】解：当0k =时，40x -+=，此时4x =，有实数根；当0k ≠时，∵方程240kx x -+=有实数根，∴△2(1)440k =--⨯⨯…，解得：116k …，此时116k …且0k ≠； 综上，116k …．故选B. 【点睛】本题考查了一元二次方程的根的判别式，熟知一元二次方程的根的判别式与根的关系是解题的关键.8．B解析：B【解析】【分析】对于一元二次方程a （x-1）2+b （x-1）-1=0，设t=x-1得到at 2+bt-1=0，利用at 2+bt-1=0有一个根为t=2019得到x-1=2019，从而可判断一元二次方程a （x-1）2+b （x-1）=1必有一根为x=2020．【详解】对于一元二次方程a （x-1）2+b （x-1）-1=0，设t=x-1，所以at 2+bt-1=0，而关于x 的一元二次方程ax 2+bx-1=0（a≠0）有一根为x=2019，所以at2+bt-1=0有一个根为t=2019，则x-1=2019，解得x=2020，所以一元二次方程a（x-1）2+b（x-1）=1必有一根为x=2020．故选B．【点睛】本题考查了一元二次方程的解：能使一元二次方程左右两边相等的未知数的值是一元二次方程的解．9．C解析：C【解析】【分析】根据题意，利用分类讨论的方法，讨论k＞0和k＜0，函数y=kx2与y=kx+k的图象，从而可以解答本题．【详解】当k＞0时，函数y=kx2的图象是开口向上，顶点在原点的抛物线，y=kx+k的图象经过第一、二、三象限，是一条直线，故选项A、B均错误，当k＜0时，函数y=kx2的图象是开口向下，顶点在原点的抛物线，y=kx+k的图象经过第二、三、四象限，是一条直线，故选项C正确，选项D错误，故选C．【点睛】本题考查二次函数的图象、一次函数的图象，解答本题的关键是明确题意，利用数形结合的思想解答．10．A解析：A【解析】【分析】【详解】解：用1，2，3三个数字组成一个三位数的所有组合是：123，132，213，231，312，321，是偶数只有2个，所以组成的三位数是偶数的概率是13；故选A．11．D 解析：D 【解析】【分析】根据中心对称图形的概念，如果把一个图形绕某一点旋转180度后能与自身重合，这个图形是中心对称图形.将④涂黑后，与图中阴影部分构成的图形绕第三个正方形的中心旋转180°后，这个图形能与自身重合，是中心对称图.【详解】解：将④涂黑后，与图中阴影部分构成的图形绕第三个正方形的中心旋转180°后，这个图形能与自身重合，是中心对称图.故选：D.【点睛】本题考查的是利用旋转设计图案，中心对称图形是要寻找对称中心，旋转180度后与原图重合.12．C解析：C【解析】【分析】【详解】解：∵弧AC=弧CD=弧DB，∴∠DOB=∠COD=∠BOE=60°，故①正确；∵AB为直径，且点E是点D关于AB的对称点∴∠E=∠ODE，AB⊥DE∴∠CED =30°=12∠DOB，故②正确；∵M和A重合时，∠MDE=60°，∴∠MDE+∠E=90°∴DM⊥CE故③不正确；根据轴对称的性质，可知D与E对称，连接CE，根据两点之间线段最短，可知这时的CM+DM最短，∵∠DOB=∠COD=∠BOE=60°∴CE为直径，即CE=10，故④正确.故选C.【点睛】本题考查了圆周角定理，圆中的有关计算问题和图形的轴对称的应用，关键是熟练地运用定理进行推理和计算，题型较好，综合性比较强，但难度不大．二、填空题13．【解析】【分析】根据一元二次方程解的定义得到a2-a-3=0b2-b-3=0即a2=a+3b2=b+3则2a3+b2+3a2-11a-b+5=2a （a+3）+b+3+3（a+3）-11a-b+5整理 解析：【解析】【分析】根据一元二次方程解的定义得到a 2-a-3=0，b 2-b-3=0，即a 2=a+3，b 2=b+3，则2a 3+b 2+3a 2-11a-b+5=2a （a+3）+b+3+3（a+3）-11a-b+5，整理得2a 2-2a+17，然后再把a 2=a+3代入后合并即可．【详解】∵a ，b 是方程x 2-x-3=0的两个根，∴a 2-a-3=0，b 2-b-3=0，即a 2=a+3，b 2=b+3，∴2a 3+b 2+3a 2-11a-b+5=2a （a+3）+b+3+3（a+3）-11a-b+5=2a 2-2a+17=2（a+3）-2a+17=2a+6-2a+17=23．14．【解析】∵x 2﹣3x+k=0有两个相等的实数根∴△=∴9﹣4k=0∴k=故答案为 解析：94【解析】 ∵x 2﹣3x +k=0有两个相等的实数根，∴△=2(3)410k --⨯⨯=，∴9﹣4k=0，∴k=94． 故答案为94． 15．3【解析】【分析】设横向的甬路宽为3x 米则纵向的甬路宽为2x 米由剩余部分的面积为144米2即可得出关于x 的一元二次方程解之取其较小值即可得出结论【详解】设横向的甬路宽为3x 米则纵向的甬路宽为2x 米根解析：3【解析】【分析】设横向的甬路宽为3x 米，则纵向的甬路宽为2x 米，由剩余部分的面积为144米2，即可得出关于x 的一元二次方程，解之取其较小值即可得出结论．【详解】设横向的甬路宽为3x 米，则纵向的甬路宽为2x 米，根据题意得：（20﹣2×2x ）（12﹣3x ）=144整理得：x 2﹣9x +8=0，解得：x 1=1，x 2=8．∵当x =8时，12﹣3x =﹣12，∴x =8不合题意，舍去，∴x =1，∴3x =3．故答案为3．【点睛】本题考查了一元二次方程的应用，找准等量关系，正确列出一元二次方程是解题的关键． 16．65°【解析】【分析】连接OAOCOD 利用同弧所对的圆心角等于圆周角得2倍求出所求的角即可【详解】解：如图解:连接OAOCOD 在圆的内接五边形ABCDE 中∠B+∠E=230°∠B=(∠AOD+∠CO解析：65°【解析】【分析】连接OA,OC,OD,利用同弧所对的圆心角等于圆周角得2倍求出所求的角即可.【详解】 解：如图解:连接OA,OC,OD,Q 在圆的内接五边形ABCDE 中, ∠B+∠E=230°,Q ∠B=12(∠AOD+∠COD), ∠E=12(∠AOC+∠COD),（圆周角定理） ∴12(∠AOD+∠COD)+ 12(∠AOC+∠COD)= 230°, 即:12（∠AOD+∠COD+∠AOC+∠COD ）= 230°， 可得：∠C0D=o o 2230360⨯-=0100，可得：∠CAD=050,在△ACD 中，AC=AD ，∠CAD=050，可得∠ACD=065,故答案：065.【点睛】此题考查了圆心角、弧、弦的关系,以及圆周角定理,熟练掌握定 理及法则是解本题的关键. 17．8x2+124x ﹣105＝0【解析】【分析】镜框所占的面积为照片面积的四分之一为了不出差错最好表示出照片的面积=4(镜框面积-照片面积)【详解】解：设镜框的宽度为xcm 依题意得：21×10＝4（21 解析：8x 2+124x ﹣105＝0【解析】【分析】镜框所占的面积为照片面积的四分之一,为了不出差错,最好表示出照片的面积=4(镜框面积-照片面积).【详解】解：设镜框的宽度为xcm,依题意,得：21×10＝4[（21+2x）（10+2x）﹣21×10],整理,得：8x2+124x﹣105＝0．故答案为：8x2+124x﹣105＝0．【点睛】本题考查了一元二次方程的应用,解题的难点在于把给出的关键描述语进行整理,解决本题的关键是要正确分析题目中等量关系.18．【解析】【分析】根据题意可以画出相应的树状图从而可以求得甲乙两人恰好分在同一组的概率【详解】如下图所示小亮和大刚两人恰好分在同一组的情况有4种共有16种等可能的结果∴小亮和大刚两人恰好分在同一组的概解析：1 4【解析】【分析】根据题意可以画出相应的树状图，从而可以求得甲、乙两人恰好分在同一组的概率．【详解】如下图所示，小亮和大刚两人恰好分在同一组的情况有4种，共有16种等可能的结果，∴小亮和大刚两人恰好分在同一组的概率是41 164，故答案为：14．【点睛】本题考查列表法与树状图法、用样本估计总体、条形统计图、扇形统计图，解答本题的关键是明确题意，找出所求问题需要的条件，利用数形结合的思想解答19．【解析】【分析】根据扇形的弧长等于圆锥的底面周长利用扇形的弧长公式即可求得圆锥的底面周长然后根据圆的周长公式即可求解【详解】解：圆锥的底面周长是：=6π设圆锥底面圆的半径是r则2πr=6π则r=3故解析：【解析】【分析】根据扇形的弧长等于圆锥的底面周长，利用扇形的弧长公式即可求得圆锥的底面周长，然后根据圆的周长公式即可求解．【详解】解：圆锥的底面周长是：9012180π⨯=6π，设圆锥底面圆的半径是r，则2πr=6π，则r=3．故答案为：3．【点睛】本题考查圆锥的计算．20．【解析】试题解析：连接OEAE∵点C为OA的中点∴∠CEO=30°∠EOC=60°∴△AEO为等边三角形∴S扇形AOE=∴S阴影=S扇形AOB-S扇形COD-（S扇形AOE-S△COE）===解析：312π+.【解析】试题解析：连接OE、AE，∵点C为OA的中点，∴∠CEO=30°，∠EOC=60°，∴△AEO为等边三角形，∴S扇形AOE=26022 3603ππ⨯=，∴S阴影=S扇形AOB-S扇形COD-（S扇形AOE-S△COE）=229029012113 36036032πππ⨯⨯---⨯（）=323 432ππ-+=3 122π+三、解答题21．（1）﹣2，1；（2）1；（3）x2﹣1＞2x﹣3【解析】【分析】（1）直接配方即可；（2）先配方得到非负数和的形式，再根据非负数的性质得到x、y的值，再求x＋y的值；（3）将两式相减，再配方即可作出判断．【详解】解：（1）x2﹣4x+5＝（x﹣2）2+1；（2）x2﹣4x+y2+2y+5＝0，（x﹣2）2+（y+1）2＝0，则x﹣2＝0，y+1＝0，解得x＝2，y＝﹣1，则x+y＝2﹣1＝1；（3）x2﹣1﹣（2x﹣3）＝x2﹣2x+2＝（x﹣1）2+1，∵（x﹣1）2≥0，∴（x﹣1）2+1＞0，∴x2﹣1＞2x﹣3．【点睛】本题考查了配方法的综合应用，配方的关键步骤是：先将一元二次方程的二次项系数化为1，然后在方程两边同时加上一次项系数一半的平方．22．（1）见解析；（2）503 25π-．【解析】【分析】（1）作OC⊥AB于点C，由OC⊥AB可知AC=BC，再根据AE=BF可知EC=FC，因为OC⊥EF，所以OE=OF，再由∠EOF=60°即可得出结论．（2）在等边△OEF中，因为∠OEF=∠EOF=60°，AE=OE，所以∠A=∠AOE=30°，故∠AOF=90°，再由AO=10可求出OF的长，根据S阴影=S扇形AOD﹣S△AOF即可得出结论．【详解】解：（1）证明：作OC⊥AB于点C，∵OC⊥AB，∴AC=BC．∵AE=BF，∴EC=FC．∵OC⊥EF，∴OE=OF．∵∠EOF=60°，∴△OEF是等边三角形．；（2）∵在等边△OEF中，∠OEF=∠EOF=60°，AE=OE，∴∠A=∠AOE=30°．∴∠AOF=90°．∵AO=10，∴OF=3103 tan10AO AOE⋅∠==．∴110350310233ACFS=⨯⨯=V,2901025360AODSππ⋅⋅==扇形．∴50325ACFAODS S Sπ∆=-=-阴影扇形．23．（1）作图见解析；裁掉的正方形的边长为2dm，底面积为12dm2；（2）当裁掉边长为2.5dm的正方形时，总费用最低，最低费用为25元．【解析】试题分析：（1）由题意可画出图形，设裁掉的正方形的边长为xdm，则题意可列出方程，可求得答案；（2）由条件可求得x的取值范围，用x可表示出总费用，利用二次函数的性质可求得其最小值，可求得答案．试题解析：（1）如图所示：设裁掉的正方形的边长为xdm，由题意可得（10﹣2x）（6﹣2x）=12，即x2﹣8x+12=0，解得x=2或x=6（舍去），答：裁掉的正方形的边长为2dm，底面积为12dm2；（2）∵长不大于宽的五倍，∴10﹣2x≤5（6﹣2x），解得0＜x≤2.5，设总费用为w元，由题意可知w=0.5×2x（16﹣4x）+2（10﹣2x）（6﹣2x）=4x2﹣48x+120=4（x﹣6）2﹣24，∵对称轴为x=6，开口向上，∴当0＜x≤2.5时，w随x的增大而减小，∴当x=2.5时，w有最小值，最小值为25元，答：当裁掉边长为2.5dm的正方形时，总费用最低，最低费用为25元．考点：1、二次函数的应用；2、一元二次方程的应用24．（1）18；（2）12【解析】【分析】（1）用树状图分3次实验列举出所有情况，再看3辆车都选择A通道通过的情况数占总情况数的多少即可；（2）由（1）可知所有可能的结果数目，再看至少有两辆汽车选择B通道通过的情况数占总情况数的多少即可．【详解】解：（1）画树状图得：共8种情况，甲、乙、丙三辆车都选择A通道通过的情况数有1种，所以都选择A通道通过的概率为18，故答案为：18；（2）∵共有8种等可能的情况，其中至少有两辆汽车选择B通道通过的有4种情况，∴至少有两辆汽车选择B通道通过的概率为41 82 ．【点睛】考查了概率的求法；用到的知识点为：概率=所求情况数与总情况数之比；得到所求的情况数是解决本题的关键．25．（1）证明见解析（2）【解析】【分析】（1）如图，连接OA；证明∠OAP=90°，即可解决问题．（2）如图，作辅助线；求出OM=1，OA=2；求出△AOB、扇形AOB的面积，即可解决问题．【详解】如图，连接OA；，；而，；而，；，，是的切线．如图，过点O作，则，，，，；，，图中阴影部分的面积．【点睛】本题考查了切线的判定与扇形面积的计算，解题的关键是熟练的掌握切线的判定与扇形面积公式.。
2020-2021学年江苏省无锡市九年级中考一模英语试题及答案
中考第一次适应性训练英语试卷第一卷客观题(共50分)一、单项填空在A、B、C、D四个选项中，选出可以填入空白处的最佳选项(本大题共14分，每小题1分)1. —Jim took _______ one-hour ride just now. What a short time he spent finishing such a long way!—He is _________ experienced rider.A. an; theB. a; anC. a; theD. an; a2. ---__________ it is from our own planet Earth to Mars!--- Yes, it takes months to travel to Mars by spacecraft.A. How soonB. How farC. How longD. How often3. Jerry is always so busy that he can hardly __________ a few minutes to talk with his child.A. spareB. shareC. spendD. save4. Driving in rush hour traffic __________ be very dangerous, so you __________ be too careful.A. should; ought toB. could; shouldC. might; mustn’tD. can; can’t5. You can’t believe how terrible the fire is __________ you see it with your own eyes.A. thoughB. becauseC. unlessD. since6. About _______ of the workers in the factory were born in the _______.A. two thirds; 1970B. two thirds; 1970sC. two third; 1970D. two third; 1970s7. Nowadays, many people prefer ________ to the countryside ________ the fresh air.A. to move; to breathingB. moving; to breathingC. to move; to breatheD. moving; to breathe8. --- How was your job interview yesterday?--- Oh, I couldn’t feel __________. I could hardly answer most of the questions they asked.A. betterB. easierC. worseD. happier9. --- Look! What a mess it is in your room!--- Sorry. I’ll __________ my school things and tidy it right now.A. put upB. put awayC. put outD. put off10. ---Did you enjoy the match?---Oh, no. When I got there, the match _______ for a quarter.A. has been overB. had endedC. had been overD. has ended11.Would you please tell me_____________________ ?A.when did he come homeB.where he would play footballC.if he had seen the filmD.why he didn’t watch the game12. Elvis Presley was famous _______ the king of rock and roll while Bruce Lee was famous _______ hiskung fu.A. for; forB. as; asC. for; asD. as; for13. The time he has devoted in the past years __________ the disabled is now consideredto be __________ great value __________ him.A. to help; of; forB. to helping; /; toC. to help; in; ofD. to helping; of; to14. --- Bill, can I get you anything to drink?--- __________.A. You are welcomeB. No problemC. I wouldn’t mind a coffeeD. It doesn’t matter.二、完形填空先通读下面的短文，掌握其大意，然后从下面四个答案中选择可以填入相应空白处的最佳答案（本大题共10分，每小题1分）Time flies so quickly! We become mature(成熟的)girls or boys, or at least we 15 we are. At the same time, our parents are no longer young.They 16 all they have to us but never look forward to getting 17 back. When we are ill in bed, they stay with us day and night. When we’re hungry or cold or sad, they 18 offer help.But what have we done for our parents? 19 we grow up, we have our own ideas and we believe we are 20 enough to think and act by ourselves, so we usually dislike their care. __21__, we don’t listen to them; sometimes even quarrel with them!We must 22 something now, letting them know that we love them too. Try our best to understand our parents, and not to make them feel hopeless. In a word, make it a duty to bring__23_ to them because that’s the sign that we are really mature.Children are parents’24 and we are carrying both our dreams and theirs. The pleasure of our parents is what we should try to achieve!15. A. think B. advise C. talk D. explain16. A. pass B. give C. show D. take17. A. something B. everything C. anything D. nothing18. A. never B. hardly C. seldom D. always19. A. If B. Before C. As D. Though20. A. careful B. old C. young D. patient21. A. At first B. As a result C. So far D. At once22. A. throw B. ask C. read D. do23. A. stress B. money C. happiness D. complaint24. A. hope B. award C. task D. aim三、阅读理解阅读下面短文，根据短文内容选择最佳答案（本大题共26分，每小题2分）AOne of the things to be learnt in a foreign language is guessing all the time what kind of thing to come when listening to someone talking. People do this all the time in their own language, so it is necessary to do this in a foreign language, too. Here are some examples.◆“What’s the matter?”“I went to a party last night, so I…”◆“I feel so tired these days.”“I think you’d better…”◆“Of course, she never stops talking. She is one of the most…”You can see from the above three examples that the context(上下文)helps a lot in understanding what is being talked about. So “guessing” is very important in understanding English, especially spoken English.( ) 25. This passage tells us mainly about _______.A. the importance of “guessing” in learning a foreign languageB. how to guess what one is going to talk aboutC. some examples of right guessingD. how important it is to guess all the time( ) 26. Which of the following best finishes the sentence in EXAMPLE 3?A. She is one of the most famous film stars.B. She is one of the most beautiful women.C. She is one of the most famous speakers.D. She is one of the most talkative women.( ) 27. From the passage we can infer(推断)that guessing is _______ in learning a foreign language.A. the only wayB. more important in spoken English than in written EnglishC. more important than any other wayD. more important in written English than in spoken EnglishBA few minutes before six o’clock, Mr. Smith decided to leave. He was about to start the car when a gunman jumped up from the back seat. He held a gun to Mr. Smith’s head. “Drive me to Paris!”he shouted.“All right”, Mr. Smith answered. He started the engine, pulled away from the side of the street and drove down. Being eighty-one years old, he knew he could not fight the gunman. He knew he needed help. Where were the police? As he drove through a crossing, he looked up and down the side streets, hoping to meet a police car. But he could see nothing. “Just my luck,” he thought, “If I was driving too fast, there would be a police car on every corner.”Suddenly he pushed his foot down on the accelerator(油门), and the car ran much faster. “What are you doing?”shouted the gunman. “Keeping off the police,”Mr. Smith answered. “I thought I saw a police car back there.”He ran lights, drove the wrong way on one-way streets. On two-way streets he drove on the wrong side of th e road. Not one policeman saw him. Again Mr. Smith’s plan was not working. He had to try a new plan. He turned a corner and saw the police station in front. Then he drove his car as fast as he could towards the police gate. The car hit a police motorbike down and stopped. Mr. Smith shouted, “Help! Help!” Then he reached back to grab(夺) the man’s gun. At the same time the policeman heard the noiseand quickly caught the gunman.28. Why did Mr. Smith drive much faster suddenly?A. Because he wanted to keep off the police.B. Because he saw a police car behind his.C. Because his plan was working.D. Because he wanted the police to see him.29. Which of the following is not TRUE?A. Mr. Smith ran lights, drove the wrong way on one-way streets.B. Mr. Smith knew he didn’t need any help.C. Mr. Smith drove his car as fast as he could towards the police gate.D. Mr. Smith looked up and down the side street, hoping to meet a police car.30. From the passage, what can we infer(推测)?A. Mr. Smith is a strong man.B. Mr. Smith is a shy man.C. Mr. Smith is a wise man.D. Mr. Smith is a stupid man.CWe don’t know how different our future will be in the future. We can only try to imagine it.At first we think about human relationship. In the year 2050, we will use computers almost every day we w ill be making new friends through the Internet—even our husbands or wives will be met in this way. It will be much faster and easier for us. On the other hand, our relationships with people won’t be as important as they are today—we will feel a little lonely.Computers will also help us in many other activities in 2050. For example, they will be used by the children at school to make their learning easier. In addition, there will be much more other machines which will play a similar role as computers, like r obots which will do the homework for us.Spending holidays will also be completely different. Traveling to other planets or to the moon will be available for everyone. Means(方式) of transport will, of course, change, too. We will be using solar-powered cars, which will be much cleaner.We could expect that the faster technological progress would lead to a more polluted environment. But it isn’t true. We will pay more attention to protecting the environment. And, scientists will probably find cures for many dangerous diseases, like cancer or AI DS. Therefore, our surroundings as well as health will be in better condition.Although we can’t predict(预测) the exact changes which will be made in the world, we often think about them. We worry about our and our children’s future; we have expectations, hopes as well as fears. But I think we should be rather sanguine(乐观的) about our future. We should be happy and believe good things will happen.31. Why will people probably feel a little lonely in 2050?A. Because the number of people will become much smaller．B. Because there will be less face-to-face communicationC. Because people won’t like making friends with each otherD. Because people won’t communicate with each other much often．32. According to the passage, which of the following will happen in 2050?A. The relationship between people will be more important than today.B. The way of spending holidays will be the same as that of today.C. It won’t be difficult for people to travel to other planets.D. Our environment will be much more polluted with a growing number of cars.33. What does the passage mainly talk about?A. How people will communicate in the year 2050.B. What our life will be like in the year 2050.C. How people will travel and spend their holidays in the year 2050.D. Wha t high technology will appear in the year 2050.DYou are probably familiar with the saying：An apple a day keeps the doctor away. A recent research carried out by the Chinese University of Hong Kong may change the saying:An apple a day may keep aging away.The research chose fruit flies(果蝇), as they share many genes(基因)with humans. The fruit flies were either fed normally or had an apple extract(浓缩物) added to their diet.It turned out that those fruit flies that were given apple extract lived about 55 days—five days longer than the flies that were normally fed. The research group also found it easier for the flies to walk，climb and move about as they aged.According to the result, the researchers believed that the antioxidants(抗氧化剂) in the appleextract helped clean up dangerous chemicals(化学物质) that cause illnesses，as well as aging.In another study，researchers examined diets of thousands of women. They discovered that those who regularly ate apples were 20 percent less likely to suffer heart illnesses and stroke.The apples’ genetic code(遗传密码) was discovered recently. It allows scientists to develop nicer and healthier fruits. Resear chers are already using the information to grow a kind of apples full of antioxidants that can keep eyes and joints healthy and protect humans against heart illnesses and cancer.Apples that kill the desire(欲望) to eat could also be produced, with the first“extra-healthy’’apples on supermarket shelves within just four or five years.The team that keeps studying apple DNA includes 100 scientists from five countries. Their research also suggests that around 65 million years ago, when dinosaurs began to die off the plant，which would finally become today’s apple tree, experienced a great genetic change. The number of many of its genes doubled. The extra genes allowed the apple to get used to worse conditions and go through a different development from peaches，strawberries and other related fruits.34．Why were fruit flies used for the research?A. Because they have a similar diet to humans.B. Because they have a history as long as apples.C. Because they share a lot of genes with humans.D. Because they feed on nothing but apple extract.35．What result did the researchers find out?A. Apples produce chemicals that can change hu man genes.B. Apples have antioxidants that kill chemicals that cause aging.C. Apples are rich in vitamins that are needed in humans’ bodies.D. Apples produce chemicals that make apples taste more delicious.36．What happened to apples around 65 million years ago according to the research?A. Their genes stopped their development as the environment got worse.B. Their genes became twice in number but they finally died off like dinosaurs.C. They experienced a great genetic change making them get used to worse conditions.D. They went through a similar development to peaches, strawberries and other related fruits. 37．What can we infer(推断)from the passage?A. Eating apples may bring us more advantages than we might believe before.B. People who have the habit of eating apples don’t need to see a doctor.C. Apples that kill the desire to eat are already available in supermarkets now.D. People will eat apples instead of peaches and strawberries from now on.第二卷（非选择题，共40分）四、词汇运用根据所给单词或所给中文写出单词的正确形式(本大题共8分，每小题1分)1. There are some people who have ________________ (固定的) ideas about things.2. The bicycle is _________ (超过) repair. It is too badly destroyed to repair.3. My teacher is a kind man of medium _______________ (高度).4. The boy never _________ (表达) himself well when he was in school, but now he does.5. He showed his _________________ (able) in drawing when he was quite young.6. We didn’t find the virus, because it is _______________ (tiny) than dust.7. I have to agree what you guessed is _______________ right. (possible)8. 1. Mary liked that film _______________ of all because there was nothing interestingin it. (little)五、动词填空用括号内所给动词的适当形式填空。
江苏牛津9A Unit1 单元测试卷
一、选择填空( ) 1. —I’d like you to tell me something about Beijing.—I’m sorry, but neither Helen nor I _________ there.A. have beenB. has beenC. have goneD. has gone( ) 2. _______ of his parents is in good health, but ______ of them work hard.A. None; allB. Neither; bothC. Neither; eitherD. Both; neither( ) 3. We’re going to Hangzhou by bus. You can come with us _______ you can meet us there later.A. butB. soC. andD. or( ) 4. — How does your brother like the sweaters?—_______ this sweater ________ that one are suitable for him. He likes them.A. Either; orB. Not only; but alsoC. Both; andD. Neither; nor( ) 5. My mother is _________ to listen to my long story.A. patient enoughB. too patientC. enough patientD. impatient enough( ) 6. —It’s every body’s duty to join in the Clean Your Pate Campaign.—Sure. We should try to ________ all the food that we’ve ordered.A. give upB. eat upC. show upD. turn up( ) 7. The man is creative enough________ so many nice toys for his daughter.A. buyingB. makingC. to buyD. to make( ) 8. — Why did you vote for Sally?— Because she is very ________ and she never shows off.A. curiousB. modestC. practicalD. proud( ) 9. Scientists are trying to ________ new ways to treat the terrible disease called H7 N9.A. talk aboutB. give upC. come up withD. look forward to( ) 10. —It’s necessary for you to take one hour’s exercise every day.— I agree ________ you.A. toB. onC. withD. about( ) 11. ________ Simon _______ Kitty speaks good Chinese, so they can talk with each other in Chinese.A. Neither; norB. Not only; but alsoC. Both; andD. Either; or( ) 12. — Sally, you wear a new dress today.— It fits me well, _______ the colour is not my favourite.A. andB. butC. soD. or( ) 13. Mr Li is a kind teacher. He devotes most of his time _______ us with our lessons.A. to helpB. to helpingC. helpD. helping( ) 14. — You have never been to Beijing before, have you?— ________, I have.A. First of allB. As a resultC. In factD. By the way( ) 15. I can buy ________ the book ________ the dictionary because I don’t have en ough money for both.A. both; andB. not only; but alsoC. either; orD. neither; nor二、完形填空The ancient people of Babylon and Egypt ____1____ the stars in the sky and created the zodiac (黄道十二宫图)____2___ years ago. At first it ___3____ count time. Later, many people used the stars to describe aperson’s ____4___ and to foretell (预言) what would happen in the future.A person’s zodiacal sign ____5___ his or her birth ____6____. Some believe this sign can tell us about a person’s character. For example, some think that a person ____7___ under the sign of Cancer (between June 22 and July 22) is kind and ____8___ .In many ____9___ in Asia, people believe the Chinese horoscope (星象) can describe character and foretell future events. In the Chinese horos cope, there are ___10____ animals. A person’s animal sign is connected to his or her birth ___11___. Each animal has a different type of character. People born in the Year of the Rat are friendly and careful. Those born in the Year of the Monkey are smart and ____12___ at making money.In Asia, a person’s blood type is also used to describe character. People ___13____ the blood type A are calm and serious, but they may be selfish. People with the blood type B are independent but may be lazy. People with the blood type AB ___14___ honest, and people with the blood type O are talkative (健谈的).Not everybody believes that star signs or blood types can describe character. But reading the horoscope can still be a lot of ____15____.( ) 1. A. study B. studied C. learned D. learn( ) 2. A. thousand of B. thousand C. thousands of D. thousands( ) 3. A. is used to B. was used for C. used to D. was used to( ) 4. A. name B. character C. age D. hobby( ) 5. A. is connected to B. connects to C. connected to D. was connected to( ) 6. A. place B. year C. date D. time( ) 7. A. was born B. were born C. is born D. born( ) 8. A. selfish B. home-loving C. silly D. disloyal( ) 9. A. countries B. cities C. towns D. schools( ) 10. A. ten B. eleven C. twelve D. thirteen( ) 11. A. week B. day C. month D. year( ) 12. A. bad B. good C. common D. little( ) 13. A. with B. within C. has D. have( ) 14. A. are B. is C. was D. were( ) 15. A. funny B. fun C. funs D. interest三、阅读理解(A)We know people of different star signs have different personalities. I read an article about the personalities of the 12 star signs, and found I liked two of them best. They are Capricorn and Aquarius. These are what I copy from the article. Read them and see if you like them!CapricornDecember 22 to January 19Capricornians are serious persons. You often work very hard and can be very sensitive (敏感的). For these reasons, you can do well in business. But you must learn not to worry about little things. You won’t marry very early because you are worried bout marrying a wrong person. But when you get married, you will be happy all your lives.AquariusJanuary 20 to February 18You are the happiest when you are needed by others and when you are successful. You want to get freedom and equality, and you will try your best to gain them. You also want to make it possible for all people to know the good things of life. You may choose a career (事业) in which you can help others or make others have better lives. You like to study philosophical religion (宗教哲学). You are an idealist (理想主义者) with beautiful dreams, but you can get happiness from the dreams only when you can make them come true. When friends share your interests and have a good discussion with you, you will be in a good mood. Creative work makes you happy.( ) 1. The introductions to the two star signs are from _______.A. a picture bookB. a diaryC. a cartoon bookD. an article( ) 2. According to the article, Aquarians are likely to become ________.A. businessmenB. actors or actressesC. doctorsD. pop stars( ) 3. Capricornians won’t marry early because _______.A. they want to live with their parentsB. they are serious, hard-working and sensitiveC. they don’t want to marry a wrong personD. they like living alone( ) 4. Judging from their birthdays, ________ is more likely to be a good businessman.A. David (March 10th).B. Amy (January 15th).C. Neil (July 25th).D. Peter (December 18th).( ) 5. Which of the following is NOT true?A. Aquarians like dreaming.B. Aquarians like creative work.C. Capricornians never worry too much.D. People of different star signs have different personalities.( B )When you’re curious about something, and want to know more about it, you can use the way of asking questions. Asking questions is the first step to make discoveries and find interesting answers. The steps below can guide you during the research.Step 1 On a note card or a piece of paper, write down the subject that you are interested in. Just get the main idea down. For example, you might write:Discover more about dinosaurs.Step 2 Next, stop and think for a moment about what you already know about your subject. List what you already know like the sentence below:(1) Dinosaurs lived long before human begins appeared.(2) Dinosaurs lived on the earth for more than 150 million years.(3) Some dinosaurs fed on plants, some on meat.Step 3 What can you do with what you want to learn? By asking questions. On your paper, start writing down questions about the dinosaurs as you think of them:(1) What’s the best weather for dinosaurs to live in?(2) How many kinds of dinosaurs are there?(3) Have dinosaurs really disappeared?Step 4 Armed with your list of questions, you can now go to the nearest library or computer to begin your research. As you learn more about your subject, you’ll probably discover some new questi ons. For example, you might discover that dinosaurs disappeared about 65 million years ago. Why? What happened? Asking new questions can help you research your subject more widely.The next time you find something interesting to research, take time to organize your thinking by asking good questions. And remember learning more always brings more questions.( ) 6. When you do some research, you should take the following steps:① list what you want to know② choose a research subject③ list what you alr eady know ④ discover new problemsA. ④③①②B. ①④③②C. ②③①④D. ③②④①( ) 7. From the passage, we know_______.A. dinosaurs appeared after human beingsB. not all the dinosaurs fed on meatC. dinosaurs lived on the earth for 65 million yearsD. dinosaurs liked warm seasons( ) 8. What does “Armed with your list of questions” mean?A. Putting your list of questions under your armB. Discussing your questions with y our classmateC. Writing down your list of questionsD. Taking your list of questions with you( ) 9. According to the passage, which one is true? _____A. You can find all the answers onlineB. Learn more, and you 11 have no questionsC. Asking questions is the only way for researchD. During the research, you may keep finding new questions( ) 10. The best title (标题) for this passage is “______”.A. Discovering DinosaursB. Asking Good QuestionsC. Finding SubjectD. Learning Steps( C )Here is how one new teacher made friends with the girls and boys in her class on the first day of school. As the bell rang, the teacher smiled at each girl and boy. Then she said in a quiet voice, “Good morning. How nice it is to have all of you in my class this year. I’d like to know each of you. I am sure we will enjoy working together. ” Everyone felt that she meant what she said because of her sweet voice and her friendly look.She told the girls and boys her name and wrote it on the blackboard. Then she told them some of the things she liked to do and she was hoping to do with them during the yearThen she said to the class, “Now you know me and the things I like and I want to know your names and the things you like. Then I will feel that I know you. ”Could you make friends by doing the same as this teacher did?One way of getting to know girls and boys in your class is to find out more about them. It is often to be friends with those people who have the same hobbies with you. You play the same games and go on journeys together.You may find that some new comers in your class mi ss their old friends and feel strange and alone. You can invite them to take a walk or to ride bikes with you. You will find many things in common to talk about. Just talking together in a friendly manner is one good way to make friends.( ) 11. How do you understand the saying “If you want a friend, be one” ?A. If you want to have a friend, try to make one be your friend.B. You can make friends by doing what a friend should do.C. You may have a friend by doing everything for him.D. When you need a friend, you have to be a friend of yourself.( ) 12. The teacher’s sweet voice and her friendly look _______.A. showed that she would like to he a friend of the girls and boysB. made every girl and boy happyC. told the girls and boys everything about herselfD. meant she wanted to tell the boys and girls something interesting( ) 13. A new comer will be your friend if _______.A. he always thinks of his old friendsB. you ask him to do somethingC. he knows you very wellD. you talk with him in a friendly way( ) 14. If you want to make friends with others, what of the following shouldn’t you do?A. You learn more about them.B. You talk with them in a friendly way.C. You have different hobbies with them.D. You try to be the same to them.( ) 15. Which is the best title of the passage?A. How to Make Friends with the StudentsB. What a Good TeacherC. Teachers and StudentsD. A Story about a New Teacher四、词汇A. 根据汉语提示、英文释义和句意，写出所缺单词。
2020-2021学年无锡市九年级阶段性测试英语模拟试题及答案
初三年级阶段性测试英语模拟试题第一卷（选择题，共50分）一、单项填空在A、B、C、D四个选项中, 选出可以填入空白处的最佳选项。
(本大题共14分，每小题1分)1. －Do you like _________ film we saw yesterday?－Certainly. I’ve never seen _________ better one before.A. a; aB. the; aC. a; theD. the; the2. －Plenty of latest news and information are often covered live on CCTV-1.－That’s true. ________important news channel CCTV-1 is!A. What anB. WhatC. What aD. How3. They’re ________ easy problems that ________ many students can solve them.A. so; soB. so; suchC. such; suchD. such; so4. －What did you do yesterday?－My brother took two friends of _____ to play chess with us. But I don’t know _____ of them.A. his; allB. him; bothC. his; eitherD. him; neither5. Your shoes under the bed _________ bad. Put them in the sun, please.A. are smelt terribleB. smell terribleC. smell terriblyD. are smelt terribly6. －Is the girl your cousin?－It _______ her. She _________ Hong Kong for a short stay.A. can’t be; has gone toB. mustn’t be; has been inC. can’t be; has been toD. should be; has gone in7. I really enjoyed your lecture, ______ there were some parts I didn’t quite understand.A. becauseB. unlessC. thoughD. after8. Luckily, the family arrived_______ the hotel _______ a cold evening.A. in; inB. in; onC. at; onD. at; in9. －People now can know what is happening in the world quickly.－You are right. With the help of the computers, news can _____ every corner of the world.A. getB. arriveC. returnD. reach10. －Do you know the lady ________ in red?－I know her no matter what she _______.A. worn; wearsB. putting on; dressesC. dressed; wearsD. wears; dresses11. －What did the doctor ask?—He asked how long _________.A. has our daughter caught a coldB. had our daughter caught a coldC. our daughter had caught a coldD. our daughter had had a cold12. －How about Mary?－She ________.A. has married for two yearsB. marries wellC. married with a rich manD. is going to marry to Billy13. —Where’s your father?—He’s gone to Beijing. And he’ll be back______ next month.A. sometimesB. some timesC. some timeD. sometime14. －Excuse me. Do you have a table for two?－I’m sorry, _______ there aren’t any seats now. Would you mind _______ for a while?A. but; waitingB. and; waitC. or; waitedD. but; to wait二、完形填空先通读下面的短文，掌握其大意，然后从下面四个答案中选择可以填入相应空白处的最佳答案。
江苏省无锡大桥实验学校牛津九年级上册期末复习卷
初三上期末模拟一、词汇运用1. Whenever someone asks him what personal ____________ (develop) is, he always has a lot to say.2. People in Palestine and Israel are all looking forward to living a ____________ (peace) life.3. That young boy was brave enough to stop a thief ____________ (steal) an iPhone 6S ou the bus.4. The war will never come to an end if they don’t ____________ (succeed) drive away the enemies.5.My ____________ (自豪) moment came when I finished my first marathon this September.6. “I tried everything I can do to get my little daughter to ____________ (安全),” cried the young mother.7. The government wants to have a better environment by ____________ (关闭) down more than 50 factories.8. Who do you think is the 10 most ____________ (高) paid athletes in the world?二、单项选择1. She is ______ new comer to ______ chemistry, but she has already made some important discoveries.A. the; theB. the; /C. a; /D. a; the2. You don’t look quite ______ today. Can you tell me what’s the matter?A.youB. yoursC. yourD. yourself3. Just ______ the saying goes, “It”s never too old to learn,” Carl Marx began to learn English in his ______.A. like; fiftiesB. as; fiftiethC. as; fiftiesD. like; fiftieth4. --They have little time to do after-school activities, ______?--______. They are all busy preparing for the exam.A. do they; YesB. do they; NoC. don’t they; YesD. don’t they; No5. Mr. Collins has just arrived, but I didn’t know he ______ until yesterday.A. was comingB. has comeC. will comeD. came6. There is no doubt that China’s population will get ______ because of the two-child policy.A. moreB. biggerC. bigD. many7. --Excuse me, but could you tell me ______?--Sorry, I don’t know. I’m new here, too.A. which was the way to the nearest shopping mallB. how long the Grand Theatre opensC. where to enjoy the natural beautyD. how do the local people celebrate Christmas8.Silk scarves feel ______, and they sell ______.A. smooth; goB. smoothly; goodC. smoothly; wellD. smooth; well9. I stood at the seaside, and watched the sun ______ in the east.A. raisingB. risingC. risesD. raises10.--Are you going to Sam’s birthday party this Saturday?--I’m not sure. I’ll go with you if I ______.A. am invitedB. will be invitedC. will inviteD. invite11. The robot can help me sweep the floor. ______ mart invention it is!A. WhatB. What aC. How aD. How12. Drivers are required ______ more carefully ______ foggy days.A. driving; onB. driving; inC. to drive; inD. to drive; on13.--Nowadays WeChat is very popular among friends.--Yes. It seems to be the best way of communication ______ people like.A. thatB. whichC. whatD. who14.--Vivian, I’d like to have your opinions about my project.--______. But I have one suggestion.A. That’s a good ideaB. I agree with youC. It looks fine to meD. Check it first三、动词填空1. --I heard lots of noise from you, Jim.--Sorry, Miss Zhao. I ____________ (discuss) with them about the project.2. I feel energetic again because I ____________ (have) a good rest. I think I can devote myself to the worknow.3. She has no idea which friend to turn to ____________ (borrow) some money.4. The Party leader ____________ (not be) able to win people’s trust unless he comes to people with cleanhands.5.Jim as well as his two brothers ____________ (choose) to perform on this year’s Spring Festival Gala theother day.6. Because of high house prices, many people would rather ____________ (rent) a house than buy one of theirown.7. More attention should be paid to ____________ (improve) the spiritual life of people in poor areas.8. A good medicine tastes bitter. ____________ (trust) those who advise you sincerely, and you will be a betterman.四、完成句子1.事实证明，可能不止一个人与这桩绑架案有关。
江苏省无锡市大桥实验中学2020-2021学年度九年级上册9AU1单元练习卷
大桥实验中学9A U1单元练习卷一、词汇1. Hey, cheer up! doesn't make any differences, (sad)2.Make sure the Wifi the computer with the Internet works well (connect )3. A miss is as a mile. Mistakes because of will lead to serious problems(care)4.After being into several groups, the students began to do experiments carefully(分)5.The long waiting hours outside the school gate make the school the parents (急躁）KEY：Sadness；connecting ；carelessness ；divided ；impatient二、单项选择1. Guilin is_______ attractive city. I have never been to ______more beautiful one.A. an; theB. a; aC. a; theD. an; a2. The town is no longer _______now because nearly half of it _______burned by the big fire.A. lively; wasB. alive; wasC. living; wereD. alive; were3.－It is said not only Mr. Brown but also his children _______Chinese when living in China?－I guess that is ______ they often practice Chinese with their Chinese teacher.A. speak; becauseB. speaks; becauseC. speak; whyD. speaks; why4. Humans are slowly polluting the whole world and there is not enough clean air ________water. We must take action, _______ things will be worse.A. and; andB. or; andC. and; orD. or; or5. It is important _______us to recommend an honest man ________our new president.A. for; forB. of; asC. for; to beD. of; to be6. The boy is always absent ________ school, though he is required _______every day.A. from; attendingB. for; to attendC. from; to attendD. for, attending7. --Do you believe house prices will drop in the following month?--It's hard to say. The public are still not surethe government has made up its mind to do so.A.if, thatB. whether, ifC. that; that D that; whether8. I took too many pills last night, so I feel too to keep working.A.asleep; sleepy B, sleeping; asleep C. sleeping,sleepy D. sleepy; sleepy9. We think that more attention should be paidthe air around us.A. to improveB. to to improveC.to improvingD. to to improving10.I want to knowA. how long has your uncle marriedB.how long it is since your uncle got marriedC.how long your uncle had been marriedD.how long your uncle has married11. it is to stay at home and watch TV in weather!A.How great fun; such a terribleB. What great fun; such terribleC.What a great fun,such terribleD.How a great fun,so terrible a12.Do you think the book is worth reading? --Yes, .A.It’s can’t be worseB.It can’t be praised too much.C.I nearly fell asleep when sleepingD.It is as good as a disasterKEY：DAADCC DCCBBB三、动词填空1. ---Did the couple appear at your birthday party yesterday?---No. Because they at their relative's wedding. (attend)2. --Turn off the TV, dear! Baby is sleeping.--There is no need. He up.(wake)3. I don't know what we should devote ourselves to the pollution. (reduce)4. What a great surprise! The father didn’t t expect that his son him a card as Father's Day gift.(mak e)5. No one else was seen call in the phone but except him at 9 last night. (answer)6. on the grass for a while and soon you will have a new idea about that. (lie)KEY：were attending；has woken；to reduce；would make ；answering ；Lie四、中译英:1.朋友有难，我们无论怎么帮忙都算不了什么。
江苏省无锡市大桥实验中学2020-2021学年度九年级上册月考9A Unit1-2英语试卷及答案
2020-2021学年江苏省无锡市大桥实验中学月考9A U1-2一、单项填空1. ---Do you know ________ man talking with our headmaster?---He is a friend of________.A. the, meB. the, mineC. a, meD. a, mine2. ---Shall we meet at the station at 8 a.m.?---l am afraid we_________. The train leaves at 10 a.m.A. mustn’tB. can'tC. needn'tD. shouldn’t3. ---Do you know________?---All of them _________ the museum.A. where are the students; have gone toB. where are the students; have been toC. where the students are; have gone toD. where the students are; have been to4._________ are crazy about listening to pop music in their spare time.A. Bill as well as Dick and LucyB. Neither Victor nor TomC. Not only Tim but also the twinsD. Either Anita or Jack5. --- Mr. Wu, could you tell me ____________?---You'd better do more speaking.A.how I can improve my EnglishB. which way can I chooseC.how I do with my EnglishD. what’s the matter with my English6.---Chocolate isn't good for your teeth.---____________________________.A. Yes, I really agreeB. No, I really agreeC. No, I think soD. Yes, I think so7.---Linda didn't invite us to her party.---_____________________? I don’t care.A. So whatB. What's onC. For whatD. What's up8.---Shall we stop for lunch_________ shall we drive on?---Let's stop for lunch, but the driver can't drink ________ drive.A. and; andB. or; andC. or; orD. and; or9.The time he has devoted in the past few years __________the disabled is now considered to be ______great value _______him.A. to help; of; forB.to helping; /; toC.to help; in; ofD.to helping; of, to10.---Was it under the tree _________ you were talking to a friend?---Yeap. But when I got back there, my bike was gone.A.thatB. whereC. whichD. while11.---Are you sure you don't mind if I ask you to look after my dog while I ________ here?---___________________________.A. leave; Yes, of courseB.am away from; Yes, of courseC. leave; No, of course notD.am away from; No, of course not12. ---1dislike music that I can't sing along with.---Me, _______.A. norB. tooC. eitherD. neither13. In the examination paper Question 2 is a________. I am sure nobody will make a mistake in it.A. difficultyB. matterC. giftD. pity14. ---Will you go to the park tomorrow?---If you don't. ___________.A.so do IB. so will IC. neither do ID. neither shall I15. ---How do you find this film?---__________________________. It goes a little slowly, though.A. On the InternetB. As advisedC. Not too badD. Guess答案：BCCCA DABDB BBCDC二、完形填空There are robots all around us, __1___ our lives easier. Some of them, like the calculator, work more quickly than human beings ___2___ . And they never make mistakes . They never get bored with doing the same job over and over again . ___3__, they never get tired . In some ways robots are better than people。
2020-2021学年江苏省无锡省九年级上学期期中物理试卷
2020-2021学年度第一学期初三物理期中测试卷2020年11月班级__________ 姓名__________一、选择题（本题共12小题，每小题2分，共24分。
各小题均只有一个正确选项）1.如图，是生活中经常使用的工具，其中属于费力杠杆的是（）2.下列数据符合实际的是（）A．家用日光灯工作时的电流约为1AB．小明同学从地上拾起一个鸡蛋举过头顶，对鸡蛋做的功大约是1 JC．某新型轿车汽油机的效率约为99%D．人以正常速度骑自行车的功率为1kw3.如图所示，用一根绳子绕过定滑轮，一端拴在钩码上，手执另一端，分别用力F1、F2、F3匀速拉起钩码。
忽略绳重与摩擦，下列说法中正确的是（）A．F1较大B．F2较大C．F3较大D．F1、F2、F3一样大4.如图所示的四种情形中，对力是否做功判断正确的是（）A．甲图中人提着滑板在平直的道路上匀速行走，人对滑板做了功B．乙图中人推着货车在平直的道路上匀速行走，人对货车做了功C．丙图中人用力搬石头但石头未被搬动，人对石头做了功D．丁图中足球离开脚后继续在空中飞行的过程中，人对足球做了功5.关于内能、温度和热量，下列说法正确的是（）A．物体吸收热量，温度一定升高B．一个物体内能增加了，一定是吸收了热量C．一碗水倒掉一半后，内能变小D．物体的温度越高，所含有的热量就越多6.2020年1月25日到2020年2月2日，从相关方案的设计完成，到正式投入使用，仅用了8天时间就建成的武汉火神山医院，彰显的不仅是中国速度，更是战胜疫情的坚强决心。
如图所示，为了在最短的时间完成地面基础建设，上百台挖掘机同时工作，其目的是增大所有挖掘机总的（）A．机械效率B．功C．功率D．有用功7.保持体温恒定有利于生物在较恶劣的环境中生存，恒温动物之所以能够保持体温恒定，其中一个重要原因是恒温动物体内水分的含量比变温动物大得多。
比如，水就大约占成人人体的70%，水之所以能够帮恒温动物不受外界环境温度影响维持恒定的体温，主要是因为水（）A．比热容大B．凝固点低C．液化时放热D．密度较大8.下列事例中，改变物体内能的途径与其他三项不同的是（）9.如图，用同一滑轮组分别将物体A和物体舍匀速提升相同的高度。
2020-2021学年度第一学期江苏省无锡市实验学校九年级期中模拟数学试卷(含解析)
求： （1）该公司员工一分钟跳绳的平均次数至少是多少； （2）该公司一名员工说：“我的跳绳成绩是我公司的中位数”请你给出该员工跳绳成绩的所在范围； （3）若该公司决定给每分钟跳绳不低于 140 个的员工购买纪念品，每个纪念品 300 元，则公司应拿出多 少钱购买纪念品． 25.某童装专卖店在销售中发现，一款童装每件进价为 80 元，销售价为 120 元时，每天可售出 20 件，为 了迎接“十一”国庆节，商店决定采取适当的降价措施，以扩大销售量，增加利润，经市场调查发现，如
．则这组数据的中位数和众数分别是（ ）
A. 4，5
B. 5，4
C. 5，5
D. 5，6
5.已知⊙O 的半径为 1，弦 AB 长为 1，则弦 AB 所对的圆周角为（ ）
A. 60°
B. 30°
C. 60°和 120°
D. 30°和 150°
6.对于一组数据 3, A. 中位数是 5
7, 5, 3, 2 ，下列说法正确的是（ ）
18.如图，在平面直角坐标系中，以点 A（0，2）为圆心，2 为半径的圆交 y 轴于点 B.已知点 C（2，0）， 点 D 为⊙A 上的一动点，以 CD 为斜边，在 CD 左侧作等腰直角三角形 CDE，连结 BC，则△BCE 面积 的最小值为________.
三、解答题（本大题共 10 小题，共 84 分．请在答题卡指定区域内作答，解答时应写出文字说明、证明 过程或演算步骤） 19.农科院为了解某种小麦的长势，从中随机抽取了部分麦苗，对苗高（单位： cm ）进行了测量．根据 统计的结果，绘制出如下的统计图①和图②．
2021江苏无锡查桥中学九上9月单元练习物理试题
2020-2021学年度9月初三物理单元练习卷第I卷（选择题）一、单选题(每题2分，共24分）1．初中生小宇同学是个高个子，拿起两个普通鸡蛋，并用2s的时间将它匀速举过头顶，这个过程中小宇对鸡蛋做的功约为（）A．0.2J B．2J C．10J D．20J2．如图所示的各类杠杆中，属于费力杠杆的是A．起子B．道钉撬C．筷子D．钢丝钳3．国际单位制中，下列对应物理量的基本单位错误的是（）A．力——牛顿N B．压强——帕斯卡PaC．功——焦耳J D．机械效率——瓦特W4．如图所示，在均匀杠杆的A处挂3个钩码，B处挂2个钩码，杠杆恰好在水平位置平衡，所有的钩码均相同，下列判断正确的是（）A．若在A、B两处的下面各加1个钩码，那么杠杆仍然平衡B．若在A、B两处的下面各减1个钩码，那么杠杆仍然平衡C．若将A、B两处所挂的钩码都远离支点移动一格，那么杠杆仍然平衡D．若在A处的下面加3个钩码，B处的下面加2个钩码，那么杠杆仍然平衡5．关于做功，下列说法正确的是（）A．运动员举着杠铃不动时，人对杠铃的支持力做了功B ．扛着一桶纯净水上楼时，人对水桶的支持力做了功C ．拉着拉杆箱在水平地面上行走时，地面对拉杆箱的支持力做了功D ．篮球离开手后继续在空中飞行的过程中，运动员对篮球做了功 6．如图所示，图中阴影部分的面积描述相应物理量正确的是（ ）A ．物体的密度B ．物体运动的路程C ．力做功的功率 D ．物体所受的压强7．一同学从一楼跑到三楼用了10s ，他的功率可能是（ ） A ．3WB ．30WC ．300WD ．3000W8．关于功、功率和机械效率，下列说法正确的是（ ） A ．机械的功率越大，做功越多B ．机械的功率越大，做功越快C ．机械的功率越大，机械的机械效率越高D ．机械的机械效率越高，机械越省力9．甲乙两个滑轮组如图所示 ，其中的每一个滑轮都相同，用它们分别将重物G 1、G 2提高相同的高度，不计滑轮组的摩擦，下列说法中正确的是（ ） A ．若G 1 = G 2，拉力做的额外功相同 B ．若G 1 = G 2，拉力做的总功相同C ．若G 1 = G 2，甲的机 械效率大于乙的机械效率D ．用甲乙其中的任何一个滑轮组提起不同的重物，机械效率不变 10．一定质量的物体在水平拉力的作用下沿水平面运动，物体运动的s t-图像如图所示。
江苏省无锡市实验学校2020-2021学年九年级上学期第一次月考数学试题(wd无答案)
江苏省无锡市实验学校2020-2021学年九年级上学期第一次月考数学试题一、单选题(★★) 1. 已知是一元二次方程的一个根，则的值为（）A．-1或2B．-1C．2D．0(★★★) 2. 一元二次方程 x 2﹣5 x+6＝0的解为（）A．x1＝2，x2＝﹣3B．x1＝﹣2，x2＝3C．x1＝﹣2，x2＝﹣3D．x1＝2，x2＝3(★★★) 3. 下列命题是真命题的是（）A．顶点在圆上的角叫圆周角B．三点确定一个圆C．圆的切线垂直于半径D．三角形的内心到三角形三边的距离相等(★★★) 4. 如图，四边形的外接圆为⊙ ，，，，则的度数为（）A．B．C．D．(★★★) 5. 如图，⊙ O的直径 CD＝20， AB是⊙ O的弦，AB⊥ CD，垂足为 M， OM： OD ＝3：5，则 AB的长为（）A．8B．12C．16D．2(★★★) 6. 如图，AB为半圆O的直径，C为半圆上的一点，OD⊥AC，垂足为D，延长OD与半圆O交于点E．若AB＝8，∠CAB＝30°，则图中阴影部分的面积为（）A．B．C．D．(★★★) 7. 从正方形铁片，截去宽的一条长方形，余下的矩形的面积是，则原来的正方形铁片的面积是（）A．B．C．D．(★) 8. 某农机厂四月份生产零件50万个，第二季度共生产零件182万个．设该厂五、六月份平均每月的增长率为 x，那么 x满足的方程是（）A．50（1+x）²=182B．50+50（1+x）+50（1+x）²=182C．50(1+2x)=182D．50+50(1+x)+550（1+x）²=182(★★★) 9. 已知圆锥的高为，母线为，且，圆锥的侧面展开图为如图所示的扇形．将扇形沿折叠，使点恰好落在上的点，则弧长与圆锥的底面周长的比值为（）A．B．C．D．(★★★) 10. 如图，在平面直角坐标系中，点在第一象限，⊙P与x轴、y轴都相切，且经过矩形的顶点C，与BC相交于点D，若⊙P的半径为5，点的坐标是，则点D的坐标是（）A．B．C．D．二、填空题(★) 11. 一元二次方程的解为__________．(★) 12. 如果关于的一元二次方程有实数根，那么的取值范围是___．(★★★) 13. 若 x 1， x 2是方程 x 2﹣4 x﹣2020＝0的两个实数根，则代数式 x 12﹣2 x 1+2 x 2的值等于_____．(★★) 14. 如图，、、、为一个正多边形的顶点，为正多边形的中心，若，则这个正多边形的边数为_______．(★★★) 15. 如图，⊙O是的外接圆，，，则的长为_____．(★★★) 16. 如图，从一块半径为的圆形铁皮上剪出一个圆周角为120°的扇形，如果将剪下来的扇形围成一个圆锥，则该圆锥的底面圆的半径为_________ ．(★★★) 17. 在等腰△ABC中，三边分别为a、b、c，其中a=4，b、c恰好是方程的两个实数根，则△ABC的周长为__________．(★★★)18. 我们知道，两点之间线段最短，因此，连接两点间线段的长度叫做两点间的距离；同理，连接直线外一点与直线上各点的所有线段中，垂线段最短，因此，直线外一点到这条直线的垂线段的长度，叫做点到直线的距离．类似地，连接曲线外一点与曲线上各点的所有线段中，最短线段的长度，叫做点到曲线的距离．依此定义，如图，在平面直角坐标系中，点到以原点为圆心，以1为半径的圆的距离为_____．三、解答题(★★) 19. 解方程：（1）（2）(★★) 20. 阅读第（1）题的解题过程，再解答第（2）题：（1）例：解方程 x 2﹣| x|﹣2＝0．解：当x≥0时，原方程可化为 x 2﹣ x﹣2＝0．解得： x 1＝2， x 2＝﹣1（不合题意．舍去）当 x＜0时，原方程可化为 x 2+ x﹣2＝0．解得： x 1＝﹣2， x 2＝1（不合题意．舍去）∴原方程的解是 x 1＝2， x 1＝﹣2．（2）请参照上例例题的解法，解方程 x 2﹣ x| x﹣1|﹣1＝0．(★★★) 21. 已知关于x的方程，(1)当取何值时，方程有两个不相等的实数根？(2)给选取一个合适的整数，使方程有两个有理根，并求出这两个根．(★★★) 22. 如图，在△ABC中，D是边BC上一点，以BD为直径的⊙O经过点A，且∠CAD=∠ABC．（1）请判断直线AC是否是⊙O的切线，并说明理由；（2）若CD=2，CA=4，求弦AB的长．(★★) 23. 如图，在中，，D是AB上一点，⊙O经过点A、C、D，交BC于点E，过点D作，交⊙O于点F，求证：（1）四边形DBCF是平行四边形（2）(★★★★) 24. 如图，在中，，以为直径的⊙O与相交于点，过点作⊙O的切线交于点．（1）求证：；（2）若⊙O的半径为，，求的长．(★★★) 25. 网店店主小李进了一批某种商品，每件进价10元.预售一段时间后发现：每天销售量（件）与售价（元/件）之间成一次函数关系：.（1）小李想每天赚取利润150元，又要使所进的货尽快脱手，则售价定为多少合适？（2）小李想每天赚取利润300元，这个想法能实现吗？为什么？(★★★) 26. 结合湖州创建文明城市要求，某小区业主委员会觉定把一块长80m，宽60m的矩形空地建成花园小广场，设计方案如图所示，阴影区域为绿化区(四块绿化区为全等的直角三角形)，空白区域为活动区，且四周出口宽度一样，其宽度不小于36m，不大于44m，预计活动区造价60元/m 2，绿化区造价50元/m 2，设绿化区域较长直角边为xm.(1)用含x的代数式表示出口的宽度.(2)求工程造价y与x的函数表达式，并直接写出x的取值范围.(3)如果业主委员会投资28.4万元，能否完成全部工程？若能，请写出x为整数的方案有多少种；若不能，请说明理由.(4)业主委员会决定在(3)设计的方案中，按最省钱的一种方案，先对四个绿化区域进行绿化，在完成了工作量的后，施工方进行了技术改进，每天的绿化面积是原计划的两倍，结果提前4天完成四个区域的绿化任务.问：原计划每天绿化多少平方米？(★★★★) 27. 如图，是的直径，点 D在上，的延长线与过点 B的切线交于点 C， E为线段上的点，过点 E的弦于点 H．（1）求证：；（2）已知，，且，求的长．(★★★) 28. 如图，在△ABC中，AB=AC，以AB为直径的半圆交AC于点D，交BC于点E，延长AE至点F，使EF=AE，连接FB、FC．（1）求证：四边形ABFC是菱形；（2）若AD= ，BE=1，求半圆的面积．。
2020-2021学年江苏省无锡市九年级(上)期中数学试卷-解析版
2020-2021学年江苏省无锡市锡山区锡东片九年级（上）期中数学试卷一、选择题（本大题共10小题，共30.0分）1.下列等式中，一定是一元二次方程的是()+1=0A. x2=1B. x2+1xC. x2+y=0D. ax2+c=0(a、c为常数)2.已知⊙O的半径为5cm，若点A到圆心O的距离为3cm，则点A()A. 在⊙O内B. 在⊙O上C. 在⊙O外D. 与⊙O的位置关系无法确定3.如图，P为圆O外一点，PA，PB分别切圆O于A，B两点，若PA=3，则PB=()A. 2B. 3C. 4D. 54.如图，△ABC中，点D、E分别在边AB、BC上，DE//AC，若DB=4，AB=6，BE=3，则BC的长是()A. 4B. 4.5C. 2.5D. 25.下列说法：①优弧比劣弧长；②三点可以确定一个圆；③长度相等的弧是等弧；④经过圆内的一个定点可以作无数条弦；其中不正确的个数是()A. 1个B. 2个C. 3个D. 4个6.如图，⊙O是△ABC的外接圆，已知∠ACO=30°，则∠B的度数是()A. 30°B. 45°C. 60°D. 75°7.某超市一月份的营业额为100万元，已知第一季度的总营业额共1000万元，如果平均每月增长率为x，则由题意列方程应为()A. 100(1+x)2=1000B. 100+100×2x=1000C. 100+100×3x=1000D. 100[1+(1+x)+(1+x)2]=10008.图O的直径AB=2点D在AB的延长线，DC与⊙O相于点C，连AC.若∠A=3°CD为()A. 13B. √33C. 2√33D. √39.如图，⊙O的直径AB=10，E在⊙O内，且OE=4，则过E点所有弦中，长度为整数的条数为()A. 4B. 6C. 8D. 1010.如图，在平面直角坐标系xOy中，A(−3,0)，B(3,0)，若在直线y=−x+m上存在点P满足∠APB=60°，则m的取值范围是()A. √6−5√3≤m≤√6+5√3B. −√6−5√3≤m≤√6+5√3C. √3−2√6≤m≤√3+2√6D. −√3−2√6≤m≤√3+2√6二、填空题（本大题共8小题，共16.0分）11.一元二次方程x2=2x的根是______．12.若两个相似多边形的对应边之比为5：2，则它们的面积比是______．13.根据疫情需要，某防疫物资制造厂原来每件产品的成本是100元，为提高的生产效率改进了生产技术，连续两次降低成本，两次降低后的成本是81元，则平均每次降低成本的百分率是______．14.在比例尺为1：10000的地图上，相距7.5cm的两地A、B的实际距离为______m.15.如图，正方形ABCD内接于⊙O，点E在AD⏜上，则∠BEC=______度．16.关于x的一元二次方程(2m−4)x2+3mx+m2−4=0有一根为0，则m=______．17.如图，在Rt△AOB中，∠AOB=90°，OA=3，OB=4，⊙O的半径为2，点P是AB边上的动点，过点P作⊙O的一条切线PC(点C为切点)，则线段PC长的最小值为______．18.如图，在Rt△ABC中，∠ACB=90°，AC=BC=6，E、F是BC的三等分点，过点C、E、F分别作AB的垂线，垂足分别为D、G、H，连接AE、AF，分别交CD、EG于M、N，记△CME的面积为S1，△ENF的面积为S2，△FHB的面积为S3，则1S1+1 S2+1S3的值是______．三、解答题（本大题共9小题，共84.0分）19.用适当的方法解一元二次方程：(1)2x2−3x=2；(2)x2+6x−111=0．20.如图，在正方形网格中，△ABC各顶点都在格点上，点A，C的坐标分别为(−5,1)、(−1,4)，结合所给的平面直角坐标系解答下列问题：(1)画出△ABC关于y轴对称的△A1B1C1；(2)画出△ABC关于原点O对称的△A2B2C2；(3)点C1的坐标是______ ；点C2的坐标是______ ；过C、C1、C2三点的圆的圆弧ĈC1C2的长是______ (保留π)．21.已知关于x的一元二次方程x2+x+m−1=0．(I)当m=0时，求方程的实数根．(Ⅱ)若方程有两个不相等的实数根，求实数m的取值范围．22.如图，在长为10cm，宽为8cm的矩形的四个角上截去四个全等的小正方形，使得留下的图形(图中阴影部分)面积是原矩形面积的80%，求所截去小正方形的边长．23.已知：如图，AB为⊙O的直径，点C、D在⊙O上，且BC=6cm，AC=8cm，∠ABD=45°．(1)求BD的长；(2)求图中阴影部分的面积．24.元旦期间，某超市销售两种不同品牌的苹果，已知1千克甲种苹果和1千克乙种苹果的进价之和为18元．当销售1千克甲种苹果和1千克乙种苹果利润分别为4元和2元时，陈老师购买3千克甲种苹果和4千克乙种苹果共用82元．(1)求甲、乙两种苹果的进价分别是每千克多少元？(2)在(1)的情况下，超市平均每天可售出甲种苹果100千克和乙种苹果140千克，若将这两种苹果的售价各提高1元，则超市每天这两种苹果均少售出10千克，超市决定把这两种苹果的售价提高x元，在不考虑其他因素的条件下，为了尽快售出且使超市销售这两种苹果共获利960元，求x的值．x−3，并且与x轴、y轴分别交于点A、B．25.已知：如图，直线l的解析式为y=34(1)求A、B两点的坐标；(2)一个圆心在坐标原点、半径为1的圆，以0.4个单位/秒的速度向x轴正方向运动，问在什么时刻与直线l相切？(3)在题(2)中，在圆开始运动的同时，一动点P从B点出发，沿射线BA方向以0.5个单位/秒的速度运动，设t秒时点P到动圆圆心的距离为s．①求s与t的关系式；②问在整个运动过程中，点P在动圆的圆面(圆上和圆内部)上，一共运动了多长时间？(直接写出答案)26.如图，在△ABC中，AB=AC，以AB为直径的⊙O交BC于点D，过点D作EF⊥AC于点E，交AB延长线于点F．(1)判断直线EF与⊙O的位置关系，并说明理由；(2)若⊙O半径为5，CD=6，求DE的长；(3)求证：BC2=4CE⋅AB．27.如图，在平面直角坐标系xOy中，边长为4的正方形ABCD的中心在原点O处，且AB//x轴，点P在正方形ABCD的边上，点P从点A处沿A→B→C→D→A→B→⋯匀速运动，以点P为圆心，以1为半径长画圆，在运动过程中：(1)当⊙P第1次与x轴相切时，则圆心P的坐标为______；(直接写出结果)(2)当圆心P的运动路程为2019时，判断⊙P与y轴的位置关系，并说明理由；(3)当⊙P第一次回到出发的位置时，即⊙P运动一周，求⊙P运动一周覆盖平面的区域的面积．答案和解析1.【答案】A【解析】解：A、正确；B、不是整式方程，则不是一元二次方程，选项错误；C、含有两个未知数，则不是一元二次方程，选项错误；D、当a=0时，不是一元二次方程，选项错误；故选A．本题根据一元二次方程的定义解答．一元二次方程必须满足四个条件：(1)未知数的最高次数是2；(2)二次项系数不为0；(3)是整式方程；(4)含有一个未知数．由这四个条件对四个选项进行验证，满足这四个条件者为正确答案．本题考查了一元二次方程的概念，判断一个方程是否是一元二次方程，首先要看是否是整式方程，然后看化简后是否是只含有一个未知数且未知数的最高次数是2．2.【答案】A【解析】解：∵OA=3cm<5cm，∴点A在⊙O内．故选：A．根据点到圆心的距离与圆的半径大小的比较，确定点A与⊙O的位置关系．本题考查的是点与圆的位置关系，根据点到圆心的距离比圆的半径小，可以确定点A在圆内．3.【答案】B【解析】解：连接OA、OB、OP，∵PA，PB分别切圆O于A，B两点，∴OA⊥PA，OB⊥PB，在Rt△AOP和Rt△BOP中，{OA=OBOP=OP，∴Rt△AOP≌Rt△BOP(HL)，∴PB=PA=3，故选：B．连接OA、OB、OP，根据切线的性质得出OA⊥PA，OB⊥PB，然后证得Rt△AOP≌Rt△BOP，即可求得PB=PA=3．本题考查了三角形全等的判定和性质，作出辅助线根据全等三角形是解题的关键．4.【答案】B【解析】解：∵DE//AC，∴DB：AB=BE：BC，∵DB=4，AB=6，BE=3，∴4：6=3：BC，∴BC=4.5，故选：B．由△ABC中，点D、E分别在边AB、BC上，DE//AC，根据平行线分线段成比例定理解答即可．此题考查了平行线分线段成比例定理，解题时注意：平行于三角形的一边，并且和其他两边(或两边的延长线)相交的直线，所截得的三角形的三边与原三角形的三边对应成比例．5.【答案】C【解析】解：①优弧比劣弧长，不一定，在同圆或等圆中结论成立，故①错误．②三点可以确定一个圆，错误，应该是过不在同一直线上的三个点确定一个圆．故②错误．③长度相等的弧是等弧，错误，长度相等的弧不一定相等，等弧的长度相等，故③错误．④经过圆内的一个定点可以作无数条弦，故④正确．故选：C．根据等弧的定义，优弧，劣弧的定义，确定圆的条件，弦的定义一一判断即可．本题考查等弧的定义，优弧，劣弧的定义，确定圆的条件，弦的定义等知识，解题的关键是熟练掌握基本概念，属于中考常考题型．6.【答案】C【解析】解：连接OA，如图，∵OA=OC，∠ACO=30°，∴∠ACO=∠CAO=30°，∴∠AOC=120°，∴∠B=60°．故选：C．连接OA，要求∠B，可求与它同弧所对的圆心角∠AOC；而∠AOC是等腰三角形AOC的顶角，在已知底角的前提下可求出顶角．本题考查了圆周角定理及三角形内角和定理的知识，解题的关键是正确地构造圆心角．7.【答案】D【解析】解：∵一月份的营业额为100万元，平均每月增长率为x，∴二月份的营业额为100×(1+x)，∴三月份的营业额为100×(1+x)×(1+x)=100×(1+x)2，∴可列方程为100+100×(1+x)+100×(1+x)2=1000，即100[1+(1+x)+(1+x)2]=1000．故选：D．先得到二月份的营业额，三月份的营业额，等量关系为：一月份的营业额+二月份的营业额+三月份的营业额=1000万元，把相关数值代入即可．考查由实际问题抽象出一元二次方程中求平均变化率的方法．若设变化前的量为a，变化后的量为b，平均变化率为x，则经过两次变化后的数量关系为a(1±x)2=b.得到第一季度的营业额的等量关系是解决本题的关键．8.【答案】D【解析】解：右图所示，连C，OC，∴∠BC=9°，∵AB=，∵AB是径，∴D=√OD2−OC2=√22−12=√3，∴OD2，∴∠D=∠CBA−D=60−30°=3°，∴OC1，∴BCD=∠A=30°，C=90°，选D．先B，OC由AB是直径，可知∠BCA=9°，而∠A=30°，易求∠CBA，又DC线，用弦切角定理可知∠CB=∠A=30°，再利用角形角质可D切线质得∠=∠A=30°，∠OCD= 9°，易得OD，由勾股定理可CD．本题考查了直径所对的周角等0、切性质、弦角定理、三角形外角性质，解题的关键连BCC，构造直角三角形AC，利勾股定解此题的关键．9.【答案】C【解析】解：∵AB=10，∵OB=OA=OC=5，过E作CD⊥AB于E，连接OC，则CD是过E的⊙O的最短的弦，∵OB⊥CD，∴∠CEO=90°，由勾股定理得：CE=√OC2−OE2=√52−42=3，∵OE⊥CD，OE过O，∴CD=2CE=6，∵AB是过E的⊙O的最长弦，AB=10，∴过E点所有弦中，长度为整数的条数为1+2+2+2+1=8，故选：C．过E作CD⊥AB于E，连接OC，则CD是过E的⊙O的最短的弦，AB是过E的⊙O的最长弦，根据勾股定理和垂径定理求出CD=6，得出弦的长度为6(1条)，7、8、9(都有2条)，10(1条)，即可得出答案．本题考查了垂径定理和勾股定理的应用，关键是能求出符合条件的所有情况．10.【答案】C【解析】解：如图，作等边三角形ABE，∵A(−3,0)，B(3,0)，∴OA=OB=3，∴E在y轴上，作等边三角形ABE的外接圆⊙Q，设直线y=−x+m与⊙Q相切，切点为P，当P与P1重合时m的值最大，当P与P2重合时m的值最小，当P与P1重合时，连接QP1，则QP1⊥直线y=−x+m，∵OA=3，∴OE=3√3，设⊙Q的半径为x，则x2=32+(3√3−x)2，解得x=2√3，∴EQ=AQ=PQ=2√3，∴OQ=√3，由直线y=−x+m可知OD=OC=m，∴DQ=m−√3，CD=√2m，∵∠ODC=∠P1DQ，∠COD=∠QP1D，∴△QP1D∽△COD，∴PQOC =QDCD，即2√3m=√3√2m，解得m=√3+2√6，当P与P2重合时，同理证得m=√3−2√6，∴m的取值范围是√3−2√6≤m≤√3+2√6，故选：C．作等边三角形ABE，然后作外接圆，求得直线y=−x+m与外接圆相切时的m的值，即可求得m的取值范围．本题考查了一次函数图象与系数的关系，圆周角定理，三角形相似的判定和性质，求得直线与外接圆相切时的m的值是解题的关键．11.【答案】x1=0，x2=2【解析】解：移项，得x2−2x=0，提公因式得，x(x−2)=0，x=0或x−2=0，∴x1=0，x2=2．故答案为：x1=0，x2=2．先移项，再提公因式，使每一个因式为0，从而得出答案．本题考查了一元二次方程的解法：解一元二次方程常用的方法有直接开平方法，配方法，公式法，因式分解法，要根据方程的特点灵活选用合适的方法．12.【答案】25：4【解析】解：∵两个相似多边形的对应边的比是5：2，∴这两个多边形的面积比是52：22，即这两个多边形的面积比是25：4，故答案为：25：4．根据相似多边形的面积的比等于相似比的平方解答即可求出结果．本题考查了相似多边形的性质，熟记相似多边形的面积的比等于相似比平方是解题的关键．13.【答案】10%【解析】解：设平均每次降低成本的百分率是x，依题意，得：100(1−x)2=81，解得：x1=0.1=10%，x2=1.9(不合题意，舍去)．故答案为：10%．设平均每次降低成本的百分率是x，根据生产该产品原来的成本价及经过连续两次降低成本后的成本价，即可得出关于x的一元二次方程，解之取其较小值即可得出结论．本题考查了一元二次方程的应用，找准等量关系，正确列出一元二次方程是解题的关键．14.【答案】750【解析】解：设AB的实际距离为x cm，∵比例尺为1：10000，∴7.5：x=1：10000，解得x=75000，75000cm=750m．故答案为：750．设AB的实际距离为x cm，根据比例尺的定义得到7.5：x=1：10000，利用比例的性质求得x的值，注意单位统一．此题考查了比例线段，用到的知识点是比例线段的性质，关键是根据比例线段的性质列出算式，注意单位的统一．15.【答案】45∠BOC，【解析】解：连接OB、OC，则∠E=12∵O是正方形外接圆的圆心，∴∠BOC=90°，∠BOC=45°．∴∠BEC=12连接OB、OC，根据正方形的性质，易得出∠BOC=90°，根据圆周角定理，可求出∠BEC= 45°．正确理解圆心角与圆周角的关系是解决本题的关键．16.【答案】−2【解析】解：∵关于x的一元二次方程(2m−4)x2+3mx+m2−4=0有一根为0，∴m2−4=0且2m−4≠0，∴(m+2)(m−2)=0且m≠2，解得：m=−2．故答案是：−2．把x=0代入已知方程列出关于m的新方程，通过解新方程来求m的值．本题考查了一元二次方程的解的定义．此题是根据一元二次方程的解的定义列出关于系数的方程，通过解方程来求系数的值．17.【答案】2√115 【解析】解：连接OP 、OC ，如图所示， ∵PC 是⊙O 的切线， ∴OC ⊥PC ， 根据勾股定理知：PC 2=OP 2−OC 2，∴当PO ⊥AB 时，线段PC 最短，∵在Rt △AOB 中，OA =3，OB =4，∴AB =5，∴∴S △AOB =12OA ⋅OB =12AB ⋅OP ，即OP =3×45=125，∵OC =2，∴PC =√OP 2−OC 2=√(125)2−22=2√115， 故答案为：2√115． 连接OP ，OC ，由PC 为圆O 的切线，利用切线的性质得到OC 与PC 垂直，利用勾股定理列出关系式，由OP 最小时，PC 最短，根据垂线段最短得到OP 垂直于AB 时最短，利用面积法求出此时OP 的值，再利用勾股定理即可求出PC 的最短值．此题考查了切线的性质，勾股定理的应用，熟练掌握切线的性质是解本题的关键，注意：圆的切线垂直于过切点的半径．18.【答案】52【解析】解：BF =EF =CE =2，△BFH 是等腰直角三角形，因而BH =2×√22=√2， S 3=1，根据CD//EG//FH ，BF =EF =CE ，则△CME 与△ENF 中，EN 、CM 边上的高都等于BH =√2，△BCD 是等腰直角三角形，因而CD =6×√22=3√2， 根据EG CD =BG BD =23，因而EG =23CD =2√2，DM EG =34，则MD =34EG =3√22，则CM=3√22，△CME的面积S1=12×CM×√2=32，同理S2=65，因而1S1+1S2+1S3的值是52．根据题意可以求出CD、EG、FH的长，△FHB是等腰直角三角形，面积容易得到，△CME 与△ENF中EN，CM边上的高都等于BH的长．根据相似三角形的性质就可以求出EN、CM的长．就可以求出两个三角形的面积．本题主要考查了相似三角形的性质，相似三角形的对应边的比相等．善于发现题目中的相似三角形是解决本题的关键．19.【答案】解：(1)2x2−3x=2，2x2−3x−2=0，(2x+1)(x−2)=0，∴2x+1=0或x−2=0，∴x1=−12，x2=2；(2)x2+6x−111=0，x2+6x+9=111+9，即(x+3)2=120，∴x+3=±2√30，∴x1=−3+2√30，x2=−3−2√30．【解析】(1)利用因式分解法求解即可；(2)利用配方法求解即可．此题考查了解一元二次方程−因式分解法，配方法，熟练掌握各自解法是解本题的关键．20.【答案】(1)△A1B1C1如图所示；(2)△A2B2C2如图所示；(3)(1,4)；(1,−4)；√17π.【解析】解：(1)见答案；(2)见答案；(3)C1(1,4)，C2(1,−4)，根据勾股定理，OC=√12+42=√17，过C、C1、C2三点的圆的圆弧是以CC2为直径的半圆，π×2OC=√17π.ĈC1C2的长=12故答案为：(1,4)；(1,−4)；√17π.【分析】(1)根据网格结构找出点A、B、C关于y轴的对称点A1、B1、C1的位置，然后顺次连接即可；(2)根据网格结构找出点A、B、C关于原点的对称点A2、B2、C2的位置，然后顺次连接即可；(3)根据平面直角坐标系写出点C1、C2的坐标，利用勾股定理求出OC的长，再根据过C、C1、C2三点的圆的圆弧是以CC2为直径的半圆，列式计算即可得解．本题考查了利用旋转变换作图，利用轴对称变换作图，以及弧长的计算，熟练掌握网格结构，准确找出对应点的位置是解题的关键．21.【答案】解：(Ⅰ)当m=0时，方程为x2+x−1=0．△=12−4×1×(−1)=5>0．∴x=−1±√5，2×1∴x 1=−1+√52，x 2=−1−√52．(Ⅱ)∵方程有两个不相等的实数根，∴△>0即(−1)2−4×1×(m −1)=1−4m +4=5−4m >0∵5−4m >0∴m <54．【解析】(Ⅰ)令m =0，用公式法求出一元二次方程的根即可；(Ⅱ)根据方程有两个不相等的实数根，计算根的判别式得关于m 的不等式，求解不等式即可．本题考查了一元二次方程的解法、根的判别式．一元二次方程根的判别式△=b 2−4ac ． 22.【答案】解：设小正方形的边长为xcm ，由题意得10×8−4x 2=80%×10×8，80−4x 2=64，4x 2=16，x 2=4．解得：x 1=2，x 2=−2，经检验x 1=2符合题意，x 2=−2不符合题意，舍去；所以x =2．答：截去的小正方形的边长为2cm ．【解析】等量关系为：矩形面积−四个全等的小正方形面积=矩形面积×80%，列方程即可求解．读懂题意，找到合适的等量关系是解决本题的关键，实际问题中需注意负值应舍去． 23.【答案】解：(1)∵AB 为⊙O 的直径，∴∠ACB =90°，∵BC =6cm ，AC =8cm ，∴AB =10cm ，∴OB =5cm ．连OD ，∵OD =OB ，∴∠ODB =∠ABD =45°，∴∠BOD =90°，∴BD =√OB 2+OD 2=5√2cm ．(2)S 阴影=S 扇形−S △OBD =90360π⋅52−12×5×5=25π−504cm 2．【解析】(1)由AB 为⊙O 的直径，得到∠ACB =90°，由勾股定理求得AB ，OB ，连OD ，得到等腰直角三角形，根据勾股定理即可得到结论；(2)根据S 阴影=S 扇形−S △OBD 即可得到结论．本题考查了圆周角定理，勾股定理，等腰直角三角形的性质，扇形的面积，三角形的面积，连接OD 构造直角三角形是解题的关键． 24.【答案】解：(1)设甲种苹果的进价为a 元/千克，乙种苹果的进价为b 元/千克，依题意，得：{a +b =183(a +4)+4(b +2)=82， 解得：{a =10b =8． 答：甲种苹果的进价为10元/千克，乙种苹果的进价为8元/千克．(2)依题意，得：(4+x)(100−10x)+(2+x)(140−10x)=960，化简，得：x 2−9x +14=0，解得：x 1=2，x 2=7，∵要尽快售出，∴x =2．答：x 的值为2．【解析】(1)设甲种苹果的进价为a 元/千克，乙种苹果的进价为b 元/千克，根据“1千克甲种苹果和1千克乙种苹果的进价之和为18元，当销售1千克甲种苹果和1千克乙种苹果利润分别为4元和2元时，陈老师购买3千克甲种苹果和4千克乙种苹果共用82元”，即可得出关于a，b的二元一次方程组，解之即可得出结论；(2)根据总利润=每千克的利润×销售数量，即可得出关于x的一元二次方程，解之取其较小值即可得出结论．本题考查了一元二次方程的应用以及二元一次方程组的应用，解题的关键是：(1)找准等量关系，正确列出二元一次方程组；(2)找准等量关系，正确列出一元二次方程．25.【答案】解：(1)解：如图所示：在y=34x−3中，令x=0，得y=−3；令y=0，得x=4，故A，B两点的坐标分别为A(4,0)，B(0,−3)．(2)设t秒时圆与直线l相切，设切点为H，圆心为C．如图所示，连接CH，则CH⊥AB.由∠CAH=∠BAO，∠CHA=∠BOA=90°，则△ACH∽△ABO，故CHOB =ACAB．①当点C在点A的左侧时，13=4−0.4t5解得t=356当点C在点A的右侧时，13=0.4t−45解得t=856综上，t=356或t=856；(3)①先证点P与动圆圆心C的连线平行于y轴．当时，s=3−0.3t当t>10时，s=0.3t−3；②203秒．(3)①设在t秒，动圆的圆心在C点处，动点在P处，此时OC=0.4t，BP=0.5t，C点的坐标为(0.4t,0)，连接PC．∵OCBP =0.4t0.5t=45，又OABA=45，∴OCBP=OABA，∴CP//OB，∴PC⊥OA，第21页，共23页∴P 点的横坐标为0.4t ，又∵P 点在直线AB 上，∴P 点的纵坐标为|0.3t −3|，即s ={3−0.3t(0≤t ≤10)0.3t −3(t >10)； ②由①知，当PC =1时，P 点在动圆上，当0≤PC <1时，P 点在动圆内． 当PC =1时，由对称性可知，有两种情况：①当P 点在x 轴下方时，PF =−(0.3t −3)=1，解之得t =203； ②当P 点在x 轴上方时，PF =0.3t −3=1，解之得：t =403． ∴当203≤t ≤403时，0≤PC ≤1，此时点P 在动圆的圆面上，所经过的时间为403−203=203． 答：动点在动圆的圆面上共经过了203秒．【解析】(1)根据题意可将A ，B 代入解析式中求出两点坐标；(2)当圆与直线相切时，根据直线l 与x 轴的角度可求出圆心坐标，然后再求出时间t ；(3)①先证点P 与动圆圆心C 的连线平行于y 轴．当0≤t ≤10时，s =3−0.3t ；当t >10时，s =0.3t −3；②可设在t 秒时，动圆的圆心在F 点处，动点在P 处，此时OF =0.4t ，BP =0.5t ，F 点的坐标为(0.4t,0)，连接PF ．因为OC BP =0.4t 0.5t =45，又OA BA =45，所以可得到OC BP =OABA ，进而可得到CP//OB ，PC ⊥OA ，所以P 点的横坐标为0.4t ，又结合P 点在直线AB 上，可得P 点的纵坐标为0.3t −3，因此可见：当PC =1时，P 点在动圆上，当0≤PC <1时，P 点在动圆内，而当PC =1时，由对称性可知，有两种情况：①当P 点在x 轴下方时，PC =−(0.3t −3)=1，解之可得t 的值，②当P 点在x 轴上方时，PC =0.3t −3=1，解之得t 的另一个值，进而可得到当203时，0≤PC ≤1，并且此时点P 在动圆的圆面上，所经过的时间为403．本题主要考查对于一次函数的应用以及对于圆和直线相切的性质的认识．解题时，对于动点问题，一定要分类讨论． 26.【答案】解：(1)EF 与⊙O 相切，理由如下：连接AD ，OD ，如图所示：∵AB 为⊙O 的直径，∴∠ADB =90°．∴AD ⊥BC ．∵AB=AC，∴CD=BD=12BC．∵OA=OB，∴OD是△ABC的中位线，∴OD//AC．∵EF⊥AC，∴EF⊥OD．∴EF与⊙O相切．(2)解：由(1)知∠ADC=90°，AC=AB=10，在Rt△ADC中，由勾股定理得：AD=√AC2−CD2=√102−62=8．∵S ACD=12AD⋅CD=12AC⋅DE，∴12×8×6=12×10×DE．∴DE=245．(3)证明：由(1)得：CD=12BC，AD⊥BC，∴∠ADC=90°，∵EF⊥AC，∴∠DEC=90°=∠ADC，∵∠C=∠C，∴△CDE∽△CAD，∴CDAC =CECD，∴CD2=CE⋅AB，∵AB=AC，∴14BC2=CE⋅AB，∴BC2=4CE⋅AB．【解析】(1)连接AD，OD，证明OD是△ABC的中位线，得出OD//AC.由已知条件证得EF⊥OD，即可得出结论；(2)根据勾股定理求出AD，再由三角形面积计算即可；(3)由(1)得CD=12BC，AD⊥BC，证明△CDE∽△CAD，得出CDAC=CECD，则CD2=CE⋅AB，第22页，共23页即可得出结论．本题是圆的综合题目，考查了圆周角定理、切线的判定、等腰三角形的性质、三角形中位线定理、勾股定理、相似三角形的判定与性质以及三角形面积等知识；熟练掌握圆周角定理和相似三角形的判定与性质是解题的关键．27.【答案】(−2,0)【解析】解：(1)当⊙P第1次与x轴相切时，圆心P在正方形的BC边上，且点P到x 轴的距离为1，∴圆心P的坐标为(−2,1)，故答案为：(−2,1)；(2)⊙P与y轴相切，理由：∵正方形ABCD的边长为4，∴⊙P运动一周时，圆心P的运动路程为4×4=16，∵2019÷16=1263，16∴⊙P运动了126周多，圆心P在AB上，且AP=3，∴圆心P的坐标为(−1,2)，∴圆心P到y轴的距离d=1，∵⊙P的半径r=1，∴d=r，∴⊙P与y轴相切；×4=32−4+π=28+π，(3)S=4×2×4−1×1×4+90π×12360∴⊙P运动一周覆盖平面的区域的面积为28+π．(1)根据切线的性质即可得到结论；(2)由题意得到⊙P运动一周时，圆心P的运动路程为4×4=16，由于2019÷16= 1263，于是得到⊙P运动了126周多，圆心P在AB上，且AP=3，得到圆心P的坐16标为(−1,2)，根据切线的判定定理即可得到结论；(3)根据正方形和扇形的面积公式即可得到结论．本题考查了切线的性质，扇形的面积的计算，正方形的性质，正确的识别图形是解题的关键．第23页，共23页。
江苏省无锡市锡山高级实验中学2020-2021学年度九年级上册 Unit1 Exercise C
9A Unit 1 exercise C一．选择。
1.- Do you have anything else to say for being late again?- No.nothing _________ sorry.A.butB.aboveC.behindD. from2.Hold on to your dreams,_________one day they may just come true.A.andB.butC.orD.so3.I think Bod is the most_________person to take the job because he can do the job well with less money and fewer people.A.popularB.suitableanizedD.careful4.A________lazy man can’t make_________money.A.too much;too muchB.much too,too muchC.too much;much tooD.much too;much too5.-My parents are crazy about Letters Alive.How about your parents?-_________my dad________my mom likes it.They like Readers.A.Not only;but alsoB.Both;andC.Neither;norD.Either;or6.Can you give me_________on how________my spoken English?A.some advices;to improveB.some advice；to improveC.anadvice;improvingD.an advice;to improve7.- Which one do you like,Eddie,blue or pink?-__________.I like orange.A.EitherB.NeitherC.BothD.None8-What are you reading?-A book about a baseball player.This guy was well__________foy his devotion to charity work.A.enjoyedB.respectedC.behavedD.expected9.-Bob,you don’t work hard at geography.-My dad says the world is changing every day,________I decide to wait till it stops.A.HoweverB.moreoverC.soD.otherwise10.-Does your English teacher chat with you on QQ?-Yes,sometimes.It’s__________we enjoy doing at the weekend.A.anythingB.everythingC.sometingD.nothing11.-I like the two dresses,but I can only afford________of them.-I guess you take the white one.A.eitherB.neitherC.allD.both12.There are many,______not enough,people in this country who have similar behavior practices.A.andB.butC.norD.or13.When do you think______?A.the best time to go thereB.is the best time to go thereC.the best time is to go thereD.go there is the best time14.-Oh,you sound just like an American.-____.Istill have trouble expressing myself.A.Yes,you’re rightB.You’re welcomeC.I don’t mindD.Wsll,not quite like that二．用both---and---,not only---but(also)---,either---or---或者neither---nor---填空：1._______________humans_______________animals can like without air.2._______________she_______________her twin sister impress the fans with their beautiful dance.3.Since last month ,_______________the students_______________the teacher has devoted most of their time to the competition.4._______________the boy_______________the girl knows the way.They are lost.5.You may choose_______________the bike_______________the toy.You can’t have the m both,kids.三.动词填空:1.When the work_______________(finish) tomorrow,we can have three days off.2.Mr Chen is patient that he spends as much time as he can_______________(explain) problems to us.3.---Dear!Why didn’t you answer my tel ephone?---Sorry!I_______________(attend) an important meeting then.4.Look!Jim,you_______________(drink) too little.Two thirds of the milk is still left in the bottle.5.This kind of rice grown here_______________(grow) well and___________(sell) out in the near future.6.Let’s go a nd see who _______________(sing)in the next room.7.I’mwondering what______________(happen) to the little girl.She looks so sad now.8.How much difficulty you had__________(spell)these new words!四.完成下列句子:1.Kitty周末不是做饭，就是洗碗。
苏科版2020-2021江苏省无锡市实验学校九年级数学上册第一次月考试卷(含答案)
2020-2021江苏省无锡市实验学校九年级数学上册第一次月考试卷解析版一、选择题（本大题共10小题，每小题3分，共计30分．在每小题所给出的四个选项中，恰有一项是符合题目要求的，请用2B铅笔把答题卷上相应的答案涂黑．）1.已知x=1是一元二次方程(m−2)x2+4x−m2=0的一个根，则m的值为（）A. -1或2B. -1C. 2D. 02.一元二次方程x2﹣5x+6＝0的解为（）A. x1＝2，x2＝﹣3B. x1＝﹣2，x2＝3C. x1＝﹣2，x2＝﹣3D. x1＝2，x2＝33.下列命题是真命题的是（）A. 顶点在圆上的角叫圆周角B. 三点确定一个圆C. 圆的切线垂直于半径D. 三角形的内心到三角形三边的距离相等4.如图，四边形ABCD的外接圆为⊙O，BC=CD，∠DAC=35°，∠ACD=45°，则∠ADB 的度数为（）A. 55°B. 60°C. 65°D. 70°5.如图，⊙O的直径CD＝20，AB是⊙O的弦，AB⊥CD，垂足为M，OM：OD＝3：5，则AB的长为（）A. 8B. 12C. 16D. 2 √916.如图，AB为半圆O的直径，C为半圆上的一点，OD⊥AC，垂足为D，延长OD与半圆O交于点E.若AB＝8，∠CAB＝30°，则图中阴影部分的面积为（）A. 43π−√3 B. 43π−2√3 C. 83π−√3 D. 83π−2√37.从正方形铁片，截去2cm宽的一条长方形，余下的矩形的面积是48cm2，则原来的正方形铁片的面积是（）A. 8cmB. 64cmC. 8cm 2D. 64cm 28.某农机厂一月份生产零件50万个，第一季度共生产零件182万个．设该厂二、三月份平均每月的增长率为x ，那么x 满足的方程是（ ）A. 50（1+x ）²=182B. 50+50（1+x ）+50（1+x ）²=182C. 50（1+2x ）=182D. 50+50（1+x ）+50（1+2x ）²=1829.已知圆锥的高为 AO ，母线为 AB ，且 OB AB =518 ，圆锥的侧面展开图为如图所示的扇形．将扇形沿 BE 折叠，使A 点恰好落在弧BC 上的F 点，则弧长 CF 与圆锥的底面周长的比值为（ ）A. 12B. 25C. 23D. 3410.如图，在平面直角坐标系中，点 P 在第一象限，⊙P 与x 轴、y 轴都相切，且经过矩形 AOBC 的顶点C ，与BC 相交于点D ，若⊙P 的半径为5，点 A 的坐标是 (0,8) ，则点D 的坐标是（ ）A. (9,2)B. (9,3)C. (10,2)D. (10,3)二、填空题（本大题共8小题，每小题2分，共计16分．不需要写出解答过程，只需把答案直接填写在答题卷相应的位置）11.一元二次方程 4x(x −2)=x −2 的解为________．12.如果关于 x 的一元二次方程 x 2−6x +m =0 有实数根，那么m 的取值范围是________．13.若x 1 ， x 2是方程x 2﹣4x ﹣2020＝0的两个实数根，则代数式x 12﹣2x 1+2x 2的值等于________.14.如图， A 、 B 、 C 、 D 为一个正多边形的顶点， O 为正多边形的中心，若 ∠ADB =18° ，则这个正多边形的边数为________.15.如图，⊙O是△ABC的外接圆，∠ABC=30°，AC=6，则弧AC的长为________.16.如图，从一块半径为1m的圆形铁皮上剪出一个圆周角为120°的扇形ABC，如果将剪下来的扇形围成一个圆锥，则该圆锥的底面圆的半径为________ m．）17.在等腰△ABC中，三边分别为a、b、c，其中a＝4，b、c恰好是方程x2﹣（2k+1）x+5（k﹣34＝0的两个实数根，则△ABC的周长为________．18.我们知道，两点之间线段最短，因此，连接两点间线段的长度叫做两点间的距离；同理，连接直线外一点与直线上各点的所有线段中，垂线段最短，因此，直线外一点到这条直线的垂线段的长度，叫做点到直线的距离．类似地，连接曲线外一点与曲线上各点的所有线段中，最短线段的长度，叫做点到曲线的距离．依此定义，如图，在平面直角坐标系中，点A(2,1)到以原点为圆心，以1为半径的圆的距离为________．三、解答题（本大题共10小题，共84分．请在答题卡指定区域内作答，解答时应写出文字说明、证明过程或演算步骤）19.解方程:（1）2x2-5x+3=0；（2）(x+1)2=4x20.阅读第（1）题的解题过程，再解答第（2）题：（1 ）例：解方程x2﹣|x|﹣2＝0.解：当x≥0时，原方程可化为x2﹣x﹣2＝0.解得：x1＝2，x2＝﹣1（不合题意.舍去）当x＜0时，原方程可化为x2+x﹣2＝0.解得：x1＝﹣2，x2＝1（不合题意.舍去）∴原方程的解是x1＝2，x1＝﹣2.（2 ）请参照上例例题的解法，解方程x2﹣x|x﹣1|﹣1＝0.21.已知关于x的方程(m+1)x2+2mx+m−3=0，（1）当m取何值时，方程有两个不相等的实数根？（2）给m选取一个合适的整数，使方程有两个有理根，并求出这两个根.22.如图，在△ABC中，D是边BC上一点，以BD为直径的⊙O经过点A，且∠CAD=∠ABC.（1）请判断直线AC是否是⊙O的切线，并说明理由；（2）若CD=2，CA=4，求弦AB的长.23.如图，在△ABC中，AC=BC，D是AB上一点，⊙O经过点A、C、D，交BC于点E，过点D 作DF//BC，交⊙O于点F，求证：（1）四边形DBCF是平行四边形（2）AF=EF24.如图，在△ABC中，AB=AC，以AB为直径的⊙O与BC相交于点D，过点D作⊙O的切线交AC于点E．（1）求证：DE⊥AC；（2）若⊙O的半径为5，BC=16，求DE的长．25.网店店主小李进了一批某种商品，每件进价10元.预售一段时间后发现：每天销售量y（件）与售价x （元/件）之间成一次函数关系：y=−2x+60 .（1）小李想每天赚取利润150元，又要使所进的货尽快脱手，则售价定为多少合适？（2）小李想每天赚取利润300元，这个想法能实现吗？为什么？26.结合湖州市创建文明城市要求，某小区业主委员会决定把一块长80m ，宽60m的矩形空地建成花园小广场，设计方案如图所示，阴影区域为绿化区（四块绿化区为全等的直角三角形），空白区域为活动区，且四周出口宽度一样，其宽度不小于36m ，不大于44m ，预计活动区造价60元/m2，绿化区造价50元/m2，设绿化区域较长直角边为xm ．（1）用含x的代数式表示出口的宽度________.（2）求工程总造价y与x的函数关系式，并直接写出x的取值范围；（3）如果业主委员会投资28.4万元，能否完成全部工程？若能，请写出x为整数的方案有多少种；若不能，请说明理由．（4）业主委员会决定在（3）设计的方案中，选择最省钱的一种方案，先对四个绿化区域进行绿化，在完后，施工方进行了技术改进，每天的绿化面积是原计划的两倍，结果提前4天完成四个成了工作量的13区域的绿化任务，问原计划每天绿化多少m2．27.如图，AB是⊙O的直径，点D在⊙O上，AD的延长线与过点B的切线交于点C ，E为线段AD上的点，过点E的弦FG⊥AB于点H ．（1）求证：∠C=∠AGD；（2）已知BC=6，CD=4，且CE=2AE，求EF的长．28.如图，在△ABC中，AB=AC，以AB为直径的半圆交AC于点D，交BC于点E，延长AE至点F，使EF=AE，连接FB、FC。
江苏省无锡市查桥中学2021届九年级第一学期第一次月考英语试卷
九年级英语阶段性检测第一卷〔选择题，共70分〕一．听力〔本大题共20分，每题1分〕I .听对话答复以下问题本局部共有10道小题，每题你将听到一段对话，每段对话听两遍。
在听每段对话前，你将有5分钟的时间阅读题目；听完后，你还有5秒钟的时间选择你认为最适宜的备选答案。
在听到“滴〞的信号后，进入下一题。
〔〕1.Which sign are they talking about?A. B. C.at will the girl probably buy for her father?A. B. C.( ) 3.What does the girl want to be when she grows up?A. B. C.( ) 4.What animal doesn’t the man like?A. B. C.’s Betty?A.An English teacherB.A girlC.A bird( ) 6.How many people are there in the girl’s family?( ) 7.Where is kate talking to the boy?A.At a post officeB.At a bus stopC.At a railway station ( ) 8.Why didn’t Tom watch the football match?A.He had to wait for his uncle.B.He went to see the film.C.He didn’t like to watch it.( ) 9.When did the boy last see Kate?A.Yesterday.st week.C.Two days ago.( ) 10.How much did the woman’s daughter pay for the coat?A.＄200B.＄150C.＄100你将听到一段对话和两篇短文，各听两遍。
无锡市大桥中学初中化学九年级上册第九单元《溶液》测试(含答案解析)
一、选择题1．(0分)[ID：133606]如图所示，将少量液体X加入到烧瓶中，观察到气球逐渐膨胀。
如下表中液体X和固体Y的组合，符合题意的是①②③④X水水水双氧水Y氯化钠氢氧化钠硝酸铵二氧化锰A．①B．③C．②③D．②④2．(0分)[ID：133603]下列关于溶液的说法错误的是（）A．与乳化作用相比，溶解能使物质混合得更均匀B．20℃时，50g水中溶解了15g的硝酸钾，则20℃时硝酸钾的溶解度是30gC．一定温度下，固体物质的溶解度不随水的质量改变而改变D．硝酸钾的饱和溶液恒温蒸发部分水后，剩余溶液溶质质量分数不变3．(0分)[ID：133602]如图是 a、b、c 三种固体物质的溶解度曲线，下列叙述正确的是A．将 a、b、c 三种物质 t1℃时的饱和溶液升温至 t 2℃，所得溶液的溶质质量分数大小关系是 a>b>cB．t2℃时 30g 物质 a 加入到 50g 水中不断搅拌，形成 80g 溶液C．t1℃时 a、b、c 三种物质的饱和溶液中含有溶质质量按由小到大的顺序排列是 b>a=c D．若 a 中混有少量 c，可以采用冷却热饱和溶液的方法提纯 a4．(0分)[ID：133569]如图所示，在盛有冷水的烧杯中放入甲、乙两支试管(试管中都有未溶解的该溶液的溶质)，若使甲试管中晶体减少，乙试管中晶体增多，需向烧杯中加入的物质是A．氯化钠B．氢氧化钠C．硝酸铵D．硝酸钾5．(0分)[ID：133565]20℃时，向盛有72g水的烧杯中加入18g固体M，充分溶解（如甲所示），进行如图所示实验（不考虑水分蒸发）。
下列说法正确的是A．甲是饱和溶液，乙是不饱和溶液B．丙和丁都是不饱和溶液C．丁中溶液溶质的质量分数为28%D．M的溶解度随温度的升高而减小6．(0分)[ID：133561]下表是小东同学进行的四个实验，其中正确的是选项操作现象结论A用pH试纸测定雨水的pH值pH小于7CO2的排放是导致酸雨的原因B将氧化铜与碳粉混合高温加热有红色物质生成说明碳有还原性C打开汽水瓶盖汽水自动喷出气体在水中的溶解度随压强的增加而减小D 向盛有红棕色NO2气体的集气瓶中加入活性炭红棕色消失碳与 NO2发生化学反应A．A B．B C．C D．D7．(0分)[ID：133559]如图是A、B、C三种物质的溶解度曲线。
无锡市大桥实验学校2020-2021学年第一学期初三化学期中考试(含解析)
初三化学一．选择题1．2010上海世博会开幕式上的精彩表演中，发生化学变化的是（）A．焰火表演B．霓虹灯表演C．音乐喷泉D．气球升空2．下列图标在塑料袋或饮料瓶上最常见的是（）A．B．C．D．3．下列物质中前者属于纯净物，后者属于混合物的一组的是（）A．氧化汞氧气B．糖水白酒C．氮气稀有气体D．铁矿石水4．下列不利于环境保护的做法是（）A．植树种草B．布袋购物C．焚烧落叶D．公交出行5．下列实验现象的描述与事实不符的是（）A．将光亮的铁钉放入硫酸铜溶液中，表面出现红色物质B．红磷在空气中燃烧产生大量白雾C．氢氧化钠溶液滴加到硫酸铜溶液中出现蓝色沉淀D．长时间暴露在空气中的镁条浸没在稀盐酸中，一会后表面出现气泡6．下列物质是由离子构成的是（）A．铁B．水C．过氧化氢D．硫酸铜7．如图所示的实验操作正确的是（）A．倾倒液体B．加热液体C．量取液体D．吸取液体8．在奥运会和各种世界重大比赛中对运动员进行兴奋剂检查的开销相当惊人，2008年北京奥运会期间用于兴奋剂检测的专款高达1800万元．诺龙是兴奋剂中的一种，其化学式是C18H26O2．下列关于诺龙的说法正确的是（）A．一个诺龙分子中含有46个原子B．诺龙中碳、氢、氧元素质量比为9：13：1C．诺龙中含有氧分子D．诺龙由18个碳原子、26个氢原子、2个氧原子构成9．如图是元素周期表的一部分，以下表述正确的是（）A．氟原子核内的中子数为9B．氟、硫、氯都是非金属元素C．氯原子的相对原子质量是35.45gD．氟和氯位于元素周期表同一周期10．成语“饮鸩止渴”中的“鸩”是指放了砒霜的酒．砒霜是砷（As）的氧化物，有剧毒．砒霜中砷的化合价是+3价，则砒霜的化学式为（）A．As2O B．AsO C．As2O3D．AsO211．下列事实及对这些事实的解释，正确的是（）A．金刚石很硬，而石墨质软﹣﹣﹣﹣﹣﹣﹣﹣﹣﹣构成的碳原子不同B．蔗糖是甜的，食醋是酸的﹣﹣﹣﹣﹣﹣﹣﹣﹣﹣不同种分子性质不同C．水银温度计测量体温度变化﹣﹣﹣﹣﹣﹣﹣﹣﹣原子的体积随温度的升高而增大D．电解水产生氢气和氧气﹣﹣﹣﹣﹣﹣﹣﹣﹣﹣﹣说明水是由氢分子和氧分子构成的12．2016年11月18日神舟十一号飞船返回舱成功着陆．偏二甲肼（C2H8N2）与N2O4反应放出的能量能把火箭送入太空，该化学方程式为C2H8N2+2N2O4═2X↑+3N2↑+4H2O↑，下列说法正确的是（）A．X的化学式为COB．偏二甲肼中碳的质量分数为40%C．该反应属于分解反应D．生成N2和H2O的质量比为14：913．中科院的全超导的“人造太阳”﹣﹣托克马克核聚变试验装置的调试运行成功，使我国在该领域的研究处于世界前列．氘和氚是核聚变的原料（氘、氚原子核内都只有1个质子，但含不同数目的中子），聚变发生后，氘、氚原子核转变为氦原子核．根据以上叙述，下列说法正确的是（）A．核聚变是化学变化B．氘原子和氚原子属于不同种元素的原子C．氘原子和氚原子是氢元素的两种不同原子D．氘原子和氚原子的相对原子质量相同14．化学概念间有包含、并列、交叉等不同关系。
江苏省无锡地区2020-2021学年上学期九年级英语第一次月考试试卷汇编：单项选择(部分答案)
江苏省无锡地区2020-2021学年上学期九年级英语第一次月考试试卷汇编单项选择江苏省无锡市查桥中学2021届九年级9月单元练习英语试题二、单项选择在A、B、C、D四个选项中，选出可以填入空白处的最佳选项，并在答题卷上填写相应的序号。
（本大题共14小题，每小题1分，共14分）21.--Which do you prefer, milk or coffee? --I like ______ of them. Tea is my favorite.A. bothB. eitherC. neitherD. all22.—What beautiful flowers! How much do they cost? —Fifty yuan ________.A. at allB. in allC. after allD. above all23. Work hard, ________you will let your parents down.A. andB. butC. orD. so24.________ it is to play with water on a hot summer day !A. How funB. How a funC. What a funD. What fun25.Not only my children but also my husband ___________crazy about football.A. isB. areC. amD. be26.He offered me some __________ , and I think it is worth __________ .A. advise, takingB. suggestions, takingC. advice, to takingD. advice, taking27.--- don’t know _______he will come tomorrow．_______he comes, I’ll tell you.---That’s a deal!A. if, IfB. whether, WhetherC. if, ThatD. if, Whether28.---What a useful dictionary ! --- How long_______ you_______ it?A. will, buyB. have, boughtC. have, hadD. did, buy29.---What did Tom say to you just now, John? ---He asked __________________.A. why I am so happy todayB. who did I play football with after schoolC. what will I do for the weekendD. if I could go to the movies with him tonight30.----Did you enjoy the outdoor training yesterday?----No, not at all! I was ________ dead after so much hard training.A. as good asB. as well asC. so good asD. so well as31. I felt so _________ yesterday evening that I fell ________ quickly.A. sleeping; asleepB. sleepy ; asleepC. asleep ; sleepyD. asleep ; sleep32. Most boys____ guns to dolls while most girls ___ have dolls than guns.A. would rather; preferB. prefer; would ratherC. would rather; would ratherD. prefer; prefer33.---My cousin is good at all his subjects at school, but he never ________.---What a ________ boy! We should learn from him.A. gets off; thoughtfulB. takes off; energeticC. shows off; modestD. puts off; curious34.—I wonder if I can learn English well.—____．All things are difficult before they are easy.A.I am afraid soB. You're slowC. It takes timeD. It's a piece of cake答案：21-34 CBCDA DACDA BBCC江苏省江阴市青阳初级中学2020-2021学年九年级上学期9月月考试卷二、单项填空在A、B、C、D 四个选项中，选出可以填入空白处的最佳答案。
无锡市大桥中学九年级数学上册第一单元《一元二次方程》测试(含答案解析)
一、选择题1．用直接开平方的方法解方程22(31)(25)x x +=-，做法正确的是（ ）A ．3125x x +=-B ．31(25)x x +=--C ．31(25)x x +=±-D ．3125x x +=±-2．方程2240x x --=经过配方后，其结果正确的是（ ）A ．()215x -=B ．()217x -=C ．()214x -=D ．()215x += 3．关于x 的一元二次方程()25410a x x ---＝有实数根，则a 满足（ ）． A ．5a ≠ B ．1a ≥且5a ≠ C ．1a ≥ D ．1a <且5a ≠ 4．下列方程属于一元二次方程的是（ ）A ．222-=x x xB ．215x x +=C ．220++=ax bx cD ．223x x += 5．等腰三角形的底边长为6，腰长是方程28150x x -+=的一个根，则该等腰三角形的周长为（ ）A ．12B ．16C ．l2或16D ．15 6．方程29180x x -+=的两个根是等腰三角形的底和腰，则这个等腰三角形的周长为（ ）A ．12B ．15C ．12或15D ．187．如图，在矩形ABCD 中，AB ＝a （a <2），BC ＝2．以点D 为圆心，CD 的长为半径画弧，交AD 于点E ，交BD 于点F ．下列哪条线段的长度是方程2240x ax +-=的一个根（ ）A ．线段AE 的长B ．线段BF 的长C ．线段BD 的长 D ．线段DF 的长8．为促进消费，重庆市政府开展发放政府补贴消费的“消费券活动”，某超市的月销售额逐步增加；据统计4月份的销售额为200万元，接下来5月，6月的月增长率相同，6月份的销售额为500万元，若设5月、6月每月的增长率为x ，则可列方程为（ ） A ．()2001500x +=B ．()2002001500x ++=C ．()22001500+=xD ．()20012500+=x9．在一幅长80cm ，宽50cm 的矩形风景画的四周镶一条金色纸边，制成一幅矩形挂图，如图所示，如果要使整个挂图的面积是5400cm 2，设金色纸边的宽为xcm ，那么x 满足的方程是（ ）A ．x 2+65x-350=0B ．x 2+130x-1400=0C ．x 2-130x-1400=0D ．x 2-65x-350=0 10．若关于x 的方程（m ﹣1）x 2+mx ﹣1＝0是一元二次方程，则m 的取值范围是（ ） A ．m ≠1B ．m ＝1C ．m ≥1D ．m ≠0 11．下列方程是一元二次方程的是（ ）A ．20ax bx c ++=B ．22(1)x x x -=-C ．2325x x y -+=D ．2210x += 12．一元二次方程x 2=4x 的解是（ ）A ．x=4B ．x=0C ．x=0或-4D ．x=0或4第II 卷（非选择题）请点击修改第II 卷的文字说明参考答案二、填空题13．方程2(3)30x x -+=的二次项系数为________，一次项系数为________，常数项为________．该方程判别式的值为_________，由此可以判断它的根的情况为___________． 14．填空：（1）214x x ++________2(7)x =+；（2）29x x -+_______=（x-____）2 15．把方程2230x x --=化为2()x h k +=的形式来求解的方法我们叫配方法，其中h ，k 为常数，那么本题中h k +的值是_________．16．一元二次方程2210x x -+=的一次项系数为_________．17．某小区2019年的绿化面积为3000m 2，计划2021年的绿化面积为4320m 2，如果每年绿化面积的增长率相同，那么这个增长率是_________．18．已知关于x 的方程2x m =有两个相等的实数根，则m =________．19．当m ______时，关于x 的一元二次方程2350mx x -+=有两个不相等的实数根． 20．参加足球联赛的每两队之间都进行两场比赛，共要比赛90场，共有________个队参加比赛．三、解答题21．若a 为方程2(13)16x =的一个正根，b 为方程22113y y -+=的一个负根，求+a b 的值．22．已知：关于x 的一元二次方程()232220-+++=tx t x t （0t >）． （1）求证：方程有两个不相等的实数根；（2）设方程的两个实数根分别为1x ，2x （其中12x x <）.若y 是关于t 的函数，且221=⋅+y t x x ，求这个函数的解析式．23．先化简，再求值：（1﹣1a ）21a a -，其中a 满足方程a 2﹣a ﹣2＝0． 24．已知m 是方程220x x --=的一个实数根，求代数式22()(1)m m m m--+的值． 对于代数式2ax bx c ++，若存在实数n ，当x=n 时，代数式的值也等于n ，则称n 为这个代数式的不变值. 例如：对于代数式2x ，当x=0时，代数式等于0；当x=1时，代数式等于1，我们就称0和1都是这个代数式的不变值. 在代数式存在不变值时，该代数式的最大不变值与最小不变值的差记作A ．特别地，当代数式只有一个不变值时，则A=0．(1)代数式22x -的不变值是________，A=________．(2)已知代数式231x bx -+，若A=0，求b 的值．25．解方程：（1）2237x x +=；（2）x(2x+5)=2x+5．26．解方程：(2)4x x x +=-【参考答案】***试卷处理标记，请不要删除一、选择题1．C解析：C【分析】一元二次方程22(31)(25)x x +=-，表示两个式子的平方相等，因而这两个数相等或互为相反数，据此即可把方程转化为两个一元一次方程，即可求解．【详解】解：22(31)(25)x x +=-开方得31(25)x x +=±-，故选：C ．【点睛】本题考查了解一元二次方程-直接开平方法，关键是将方程右侧看做一个非负已知数，根据法则：要把方程化为“左平方，右常数，先把系数化为1，再开平方取正负，分开求得方程解”来求解．2．A解析：A【分析】配方法的一般步骤：（1）把常数项移到等号的右边；（2）把二次项的系数化为1；（3）等式两边同时加上一次项系数一半的平方．【详解】解：∵x 2﹣2x ﹣4＝0，∴x 2﹣2x ＝4，∴x 2﹣2x +1＝4+1，∴（x ﹣1）2＝5．故选：A ．【点睛】此题考查了配方法解一元二次方程，解题时要注意解题步骤的准确应用．选择用配方法解一元二次方程时，最好使方程的二次项的系数为1，一次项的系数是2的倍数． 3．B解析：B【分析】由方程有实数根可知根的判别式b 2-4ac≥0，结合二次项的系数非零，可得出关于a 一元一次不等式组，解不等式组即可得出结论．【详解】解：由已知得：()()()25044510a a -≠⎧⎪⎨--⨯-⨯-≥⎪⎩， 解得：a≥1且a≠5．故选：B ．【点睛】本题考查了根的判别式，解题的关键是得出关于a 的一元一次不等式组．本题属于基础题，难度不大，解决该题型题目时，由根的判别式结合二次项系数非零得出不等式组是关键．4．D解析：D【分析】一元二次方程必须满足两个条件：（1）未知数的最高次数是2；（2）二次项系数不为0．据此判断即可．【详解】解：A 、移项得：20x -=，是一元一次方程，不是一元二次方程，故本选项错误； B 、不是整式方程，即不是一元二次方程，故本选项错误；C 、ax 2+bx+c=0，当a=0时，它不是一元二次方程，故C 错误；D223+=符合一元二次方程的定义，故D正确；x x故选：D．【点睛】本题考查了一元二次方程的概念，判断一个方程是否是一元二次方程，首先要看是否是整式方程，然后看化简后是否是只含有一个未知数且未知数的最高次数是2．5．B解析：B【分析】利用因式分解法解方程求出x的值，再根据等腰三角形的概念和三角形三边关系确定出三角形三边长度，继而得出答案．【详解】解：∵x2-8x+15=0，∴（x-3）（x-5）=0，则x-3=0或x-5=0，解得x1=3，x2=5，①若腰长为3，此时三角形三边长度为3、3、6，显然不能构成三角形，舍去；②若腰长为5，此时三角形三边长度为5、5、6，可以构成三角形，所以该等腰三角形的周长为5+5+6=16，故选：B．【点睛】本题主要考查等腰三角形的概念、三角形三边的关系、解一元二次方程的能力，熟练掌握解一元二次方程的几种常用方法：直接开平方法、因式分解法、公式法、配方法，结合方程的特点选择合适、简便的方法是解题的关键．6．B解析：B【分析】首先求出方程的根，再根据三角形三边关系定理列出不等式，确定是否符合题意．【详解】解：解方程x2-9x+18=0，得x1=3，x2=6，当3为腰，6为底时，不能构成等腰三角形；当6为腰，3为底时，能构成等腰三角形，周长为6+6+3=15．故选：B．【点睛】本题考查了解一元二次方程，从边的方面考查三角形，涉及分类讨论的思想方法．求三角形的周长，不能盲目地将三边长相加起来，而应养成检验三边长能否组成三角形的好习惯，把不符合题意的舍去．7．B解析：B【分析】根据勾股定理求出BF ，利用求根公式解方程，比较即可．【详解】解：∵四边形ABCD 是矩形∴CD=AB=a在Rt △BCD 中，由勾股定理得，BD =∴a ，解方程2240x ax +-=得x a =±=- ∴线段BF 的长是方程2240x ax +-=的一个根．故选：B ．【点睛】本题考查的是勾股定理、一元二次方程的解法，掌握一元二次方程的求根公式、勾股定理是解题的关键．8．C解析：C【分析】根据“4月份的销售额为200万元，接下来5月，6月的月增长率相同，6月份的销售额为500万元”，可以列出相应的一元二次方程，本题得以解决．【详解】解：由题意可得，200（1+x ）2＝500，故选：C ．【点睛】本题考查由实际问题抽象出一元二次方程，解答本题的关键是明确题意，列出相应的方程，这是一道典型的增长率问题，是中考常考题．9．A解析：A【分析】本题可设长为（80+2x ），宽为（50+2x ），再根据面积公式列出方程，化简即可．【详解】解：依题意得：（80+2x ）（50+2x ）=5400，即4000+260x+4x 2=5400，化简为：4x 2+260x-1400=0，即x 2+65x-350=0．故选：A ．【点睛】本题考查的是一元二次方程的应用，解此类题目要注意运用面积的公式列出等式再进行化简．10．A解析：A【分析】根据一元二次方程的定义可得m﹣1≠0，再解即可．【详解】解：由题意得：m﹣1≠0，解得：m≠1，故选：A．【点睛】本题考查了一元二次方程的定义，注意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．11．D解析：D【分析】根据“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：进行判断即可．【详解】解：A、当a=0时，该方程不是一元二次方程，故本选项不符合题意．B、该方程化简整理后是一元一次方程，故本选项不符合题意．C、该方程含有2个未知数，不是一元二次方程，故本选项不符合题意．D、该方程符合一元二次方程的定义，故本选项符合题意．故选：D．【点睛】本题主要考查了一元二次方程，判断一个方程是否是一元二次方程应注意抓住5个方面：“化简后”；“一个未知数”；“未知数的最高次数是2”；“二次项的系数不等于0”；“整式方程”．12．D解析：D【分析】先移项，利用因式分解法解一元二次方程.【详解】解：x2=4xx2-4x=0x（x-4）=0x=0或x=4，故选：D.【点睛】此题考查解一元二次方程，直接开平方法，配方法，公式法，因式分解法，根据一元二次方程的特点选择恰当的解法是解题的关键.二、填空题13．2-6312有两个不相等的实数根【分析】先将方程化为一般形式再计算出判别式的值根据结果判断根的情况【详解】解：化简可得：二次项系数为2一次项系数为-6常数项为3该方程判别式的值为由此可以判断它的根的解析：2 -6 3 12 有两个不相等的实数根【分析】先将方程化为一般形式，再计算出判别式的值，根据结果判断根的情况．【详解】解：化简可得：22630x x -+=，二次项系数为2，一次项系数为-6，常数项为3， 该方程判别式的值为()2642312--⨯⨯=，由此可以判断它的根的情况为：有两个不相等的实数根，故答案为：2；-6；3；12；有两个不相等的实数根．【点睛】本题考查了一元二次方程，解题的关键是掌握定义和根的判别式． 14．49【分析】运用配方法的运算方法填写即可【详解】解：（1）x2+14x+49=（x+7）2故答案为：49；（2）x2-9x+=（x-）2故答案为：【点睛】此题主要考查了配方法的应用熟练掌握完全平方公解析：49814 92 【分析】运用配方法的运算方法填写即可．【详解】解：（1）x 2+14x+49=（x+7）2故答案为：49；（2）x 2-9x+814=（x-92）2， 故答案为：814，92． 【点睛】此题主要考查了配方法的应用，熟练掌握完全平方公式是关键． 15．3【分析】首先把常数项移到等号右边经配方h 和k 即可求得进而通过计算即可得到答案【详解】根据题意移项得配方得：即∴∴故答案是：3【点睛】本题考查了配方法解一元二次方程的知识；解题的关键是熟练掌握配方法 解析：3【分析】首先把常数项移到等号右边，经配方，h 和k 即可求得，进而通过计算即可得到答案．【详解】根据题意，移项得223x x -=，配方得：22131x x -+=+，即2(1)4x -=，∴1h =-，4k =∴143h k +=-+=故答案是：3．【点睛】本题考查了配方法解一元二次方程的知识；解题的关键是熟练掌握配方法的性质，从而完成求解． 16．-2【分析】根据一元二次方程的一次项系数的定义即可求解【详解】解：一元二次方程x2－2x ＋1＝0一次项系数是：－2故答案为：－2【点睛】此题考查了一元二次方程的一般形式准确掌握一般式中的相关概念是解解析：-2【分析】根据一元二次方程的一次项系数的定义即可求解．【详解】解：一元二次方程x 2 －2x ＋1＝0一次项系数是：－2．故答案为：－2．【点睛】此题考查了一元二次方程的一般形式，准确掌握一般式中的相关概念是解题的关键． 17．20【分析】设每年绿化面积的增长率为x 根据该小区2019年及2021年的绿化面积即可得出关于x 的一元二次方程解之取其正值即可得出结论【详解】解：设每年绿化面积的增长率为x 依题意得：3000（1+x ）解析：20%【分析】设每年绿化面积的增长率为x ，根据该小区2019年及2021年的绿化面积，即可得出关于x 的一元二次方程，解之取其正值即可得出结论．【详解】解：设每年绿化面积的增长率为x ，依题意，得：3000（1+x ）2=4320，解得：x 1=0.2=20%，x 2=-2.2（不合题意，舍去）．故答案为：20%．【点睛】本题考查了一元二次方程的应用，找准等量关系，正确列出一元二次方程是解题的关键． 18．0【分析】先将方程化成一般式然后再运用根的判别式求解即可【详解】解：∵关于的方程有两个相等的实数根∴关于的方程有两个相等的实数根∴△=02-4m=0解得m=0故答案为0【点睛】本题主要考查了一元二次 解析：0【分析】先将方程化成一般式，然后再运用根的判别式求解即可．【详解】解：∵关于x的方程2x m=有两个相等的实数根，∴关于x的方程20x m-=有两个相等的实数根，∴△=02-4m=0，解得m=0．故答案为0．【点睛】本题主要考查了一元二次方程根的判别式，掌握“当△=0时，方程有两个相等的实数根”是解答本题的关键．19．m＜且m≠0【分析】根据一元二次方程的定义及判别式的意义得出m≠0且△=（-3）2-4m×5=9-20m＞0解不等式组确定m的取值范围【详解】解：∵关于x的一元二次方程mx2-3x+5=0有两个不相解析：m＜920且m≠0．【分析】根据一元二次方程的定义及判别式的意义得出m≠0，且△=（-3）2-4m×5=9-20m＞0，解不等式组，确定m的取值范围．【详解】解：∵关于x的一元二次方程mx2-3x+5=0有两个不相等的实数根，∴m≠0，且△=（-3）2-4m×5=9-20m＞0，解得m＜920且m≠0，故当m＜920且m≠0时，关于x的一元二次方程mx2-3x+5=0有两个不相等的实数根．故答案是：m＜920且m≠0．【点睛】本题考查了根的判别式，一元二次方程ax2+bx+c=0（a≠0）的根与△=b2-4ac有如下关系：（1）△＞0⇔方程有两个不相等的实数根；（2）△=0⇔方程有两个相等的实数根；（3）△＜0⇔方程没有实数根．20．10【分析】设共有x个队参加比赛根据每两队之间都进行两场比赛结合共比了90场即可得出关于x的一元二次方程解之即可得出结论【详解】解：设共有x个队参加比赛根据题意得：2×x（x-1）=90整理得：x2解析：10．【分析】设共有x个队参加比赛，根据每两队之间都进行两场比赛结合共比了90场即可得出关于x 的一元二次方程，解之即可得出结论．【详解】解：设共有x 个队参加比赛，根据题意得：2×12x （x-1）=90， 整理得：x 2-x-90=0，解得：x=10或x=-9（舍去）．故答案为：10．【点睛】本题考查了一元二次方程的应用，根据每两队之间都进行两场比赛结合共比了90场列出关于x 的一元二次方程是解题的关键．三、解答题21．a+b= 5【分析】先求出2(16x =的根4x ，由a 为方程2(16x =的一个正根，得4a =+，再求22113y y -+=的根=1y ±b 为方程22113y y -+=的一个负根，得1b =+a b 即可．【详解】2(16x -=，4x -=±，4x ，a 为方程2(16x =的一个正根，4a =+，22113y y -+=，()2113y -=，1y -==1y ±b 为方程22113y y -+=的一个负根，1b =415a b +=+=．【点睛】本题考查一元二次方程的解法，会比较方程根的正负与大小，掌握一元二次方程的解法是解题关键．22．（1）证明见解析；（2）222 1.y t t =++【分析】（1）先求解()2242b ac t =-=+，再证明＞0，即可得出结论； （2）把原方程化为：()()1220,x tx t ---=再解方程，根据0t >，12x x <，确定12,x x ，最后代入函数解析式即可得到答案．【详解】（1）证明： ()232220-+++=tx t x t ， (),32,22,a t b t c t ∴==-+=+()()22=43242+2b ac t t t ∴-=-+-⎡⎤⎣⎦22912488t t t t =++--244t t =++()22t =+， t ＞0，()22t ∴=+＞0，所以原方程有两个不相等的实数根．（2） ()232220-+++=tx t x t ， ()()1220,x tx t ∴---=10x ∴-=或220,tx t --=1x ∴=或22,x t=+ 0t >，22t∴+＞1，12x x <，1221,2,x x t∴==+ ∴ 221=⋅+y t x x2221t t ⎛⎫=++ ⎪⎝⎭ 222 1.t t =++【点睛】本题考查的一元二次方程根的判别式，利用因式分解法解一元二次方程，不等式的性质，列函数关系式，掌握以上知识是解题的关键．23．11a +，13． 【分析】先根据分式的基本性质化简，再求解关于a 的一元二次方程，代入求解即可；【详解】 解：原式＝()()11111a a a a a a -=++-， 解方程a 2﹣a ﹣2＝0得，a 1＝2，a 2＝﹣1，当a ＝2时，原式＝11=2+13， 当a ＝﹣1时，分式无意义， 则分式的值为13． 【点睛】本题主要考查了分式化简求值，与一元二次方程的求解，准确分析计算是解题的关键．24．（1）-1，2；3；（2）11b =-+21b =--【分析】（1）根据不变值的定义可得出关于x 的一元二次方程，解之即可求出x 的值，再作差后可求出A 的值；（2）由A=0可得出方程23(1)1x b x -++=0有两个相等的实数根，进而可得出△=0，解答即可得出结论．【详解】解：（1）根据题意得，220x x --=，解得，11x =-，22x =∴A=2-（1）=2+1=3，故答案为：-1，2；3；（2）根据题意得，23(1)1x b x -++=0有两个相等的实数根，∴△=[- (b+1)]2-4×3×1=0∴11b =-+21b =--【点睛】本题考查了一元二次方程的应用以及根的判别式，根据不变值的定义，求出一元二次方程的解是解题的关键．25．（1）112x =，23x =；（2）11x =，252x =- 【分析】（1）先把方程化为一般式，然后利用因式分解法解方程；（2）利用因式分解法求解．【详解】解：（1）2x 2-7x+3=0，（2x-1）（x-3）=0，2x-1=0或x-3=0，所以x 1=12，x 2=3； （3）移项得，x （2x+5）-（2x+5）=0，因式分解得，（2x+5）（x-1）=0，∴x-1=0，2x+5=0，∴11x =，252x =-； 【点睛】本题考查了解一元二次方程的能力，熟练掌握解一元二次方程的几种常用方法：直接开平方法、因式分解法、公式法、配方法，结合方程的特点选择合适、简便的方法是解题的关键． 26．1241x x =-=，【分析】方程整理后，利用因式分解法求解即可．【详解】解：(2)4x x x +=-，方程整理得：2340x x +-=，因式分解得：()()410x x +-=，则40x +=或10x -=，∴1241x x =-=，．【点睛】本题考查了解一元二次方程－因式分解法：因式分解法就是利用因式分解求出方程的解的方法，这种方法简便易用，是解一元二次方程最常用的方法．。
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大桥实验中学9A U1单元练习卷一、词汇1. Hey, cheer up! doesn't make any differences, (sad)2.Make sure the Wifi the computer with the Internet works well (connect )3. A miss is as a mile. Mistakes because of will lead to serious problems(care)4.After being into several groups, the students began to do experiments carefully(分)5.The long waiting hours outside the school gate make the school the parents (急躁）KEY：Sadness；connecting ；carelessness ；divided ；impatient二、单项选择1. Guilin is_______ attractive city. I have never been to ______more beautiful one.A. an; theB. a; aC. a; theD. an; a2. The town is no longer _______now because nearly half of it _______burned by the big fire.A. lively; wasB. alive; wasC. living; wereD. alive; were3.－It is said not only Mr. Brown but also his children _______Chinese when living in China?－I guess that is ______ they often practice Chinese with their Chinese teacher.A. speak; becauseB. speaks; becauseC. speak; whyD. speaks; why4. Humans are slowly polluting the whole world and there is not enough clean air ________water. We must take action, _______ things will be worse.A. and; andB. or; andC. and; orD. or; or5. It is important _______us to recommend an honest man ________our new president.A. for; forB. of; asC. for; to beD. of; to be6. The boy is always absent ________ school, though he is required _______every day.A. from; attendingB. for; to attendC. from; to attendD. for, attending7. --Do you believe house prices will drop in the following month?--It's hard to say. The public are still not surethe government has made up its mind to do so.A.if, thatB. whether, ifC. that; that D that; whether8. I took too many pills last night, so I feel too to keep working.A.asleep; sleepy B, sleeping; asleep C. sleeping,sleepy D. sleepy; sleepy9. We think that more attention should be paidthe air around us.A. to improveB. to to improveC.to improvingD. to to improving10.I want to knowA. how long has your uncle marriedB.how long it is since your uncle got marriedC.how long your uncle had been marriedD.how long your uncle has married11. it is to stay at home and watch TV in weather!A.How great fun; such a terribleB. What great fun; such terribleC.What a great fun,such terribleD.How a great fun,so terrible a12.Do you think the book is worth reading? --Yes, .A.It’s can’t be worseB.It can’t be praised too much.C.I nearly fell asleep when sleepingD.It is as good as a disasterKEY：DAADCC DCCBBB三、动词填空1. ---Did the couple appear at your birthday party yesterday?---No. Because they at their relative's wedding. (attend)2. --Turn off the TV, dear! Baby is sleeping.--There is no need. He up.(wake)3. I don't know what we should devote ourselves to the pollution. (reduce)4. What a great surprise! The father didn’t t expect that his son him a card as Father's Day gift.(mak e)5. No one else was seen call in the phone but except him at 9 last night. (answer)6. on the grass for a while and soon you will have a new idea about that. (lie)KEY：were attending；has woken；to reduce；would make ；answering ；Lie四、中译英:1.朋友有难，我们无论怎么帮忙都算不了什么。
We______________________________________when they are in trouble.2.大卫太聪明了,不费吹灰之力就解出了这道数学难题。
David was so clever_____________________________ the math problem.3.因过多赞美而骄傲自满____________________________________________________________4.从不理会那些对现状不满的人____________________________________________________________5.喜欢夸夸其谈而无所事事____________________________________________________________6.给学生们重复语法规则不厌其烦____________________________________________________________7.习惯在微信里炫耀她的日常生活____________________________________________________________8.整日废寝忘食地劳作很糟糕____________________________________________________________9.既不好沟通也不易共事____________________________________________________________10.不仅对我自己也对我的家庭都是巨大挑战____________________________________________________________11.离开公司后把所有时间投入于剧本写作____________________________________________________________Keys:1.can’t help our friends too much2.that he had no difficulty in working out3.be proud because of too much praise4.pay no attention to those who are not happy withthe present situation5.like talking much but do nothing6.be patient enough to repeat grammar rules for students7.be used to showing off her daily life on Wechat8.be terrible to work without sleeping or eating the whole day9.be neither easy to communicate with nor easy to work with10.a big challenge not only to myself but also to my family11.devote oneself to writing plays after leaving the company。