资源简介 榆次区2024年九年级第二次模拟测试题(卷)数学姓名准考证号注意事项:1.本试卷共8页,满分120分,考试时间120分钟2.答卷前,考生务必将自己的姓名,准考证号填写在本试卷相应的位置,3.答案全部在答题卡上完成,答在本试卷上无效4考试结束后,将本试卷和答题卡一并交回.一、选择题(本大题共10个小题,每小题3分,共30分.在每个小题给出的四个选项中,只有一项符合题目要求,请选出并在答题卡上将该项涂黑)1,有理数-1的相反数是A月BC.-2D.22近年来,全球新能源汽车发展如火如茶,我国新能源汽车产业异军突起,2024年1至2月,我国新能源汽车销量占世界新能源汽车销量的62%.下列图案是我国四款新能源汽车的标志,其中既是轴对称图形又是中心对称图形的是B3.下列运算正确的是A.a2ta=asB.(-a2)3=-aC.5-√5=2D.V6xV3=3√24.小明五一假期在某博物馆看到了如图1所示的展品,了解到它是我国古代官仓、粮栈、米行等进行粮食计量的必备工具—米斗,凝聚着中国人上千年的智慧和匠心精神,且正面有着吉祥的寓意,是丰饶富足的象征.其示图1图2意图(不记厚度)如图2所示,则其俯视图为九年级数学试题第1页(共8页)BD5某城市湿地公园的湖中有两个小岛A,B,湖边有一北北观景台C(如图),其中观景台C在小岛A的南偏东30°方向,在小岛B的南偏西50°方向,则∠ACB的度数是A.20°B.50°C.80°D.90°6.随着科技发展,人工智能已经悄然运用在各行各业某款国产人工智能软件包含文学创作、数理逻辑推算、中文理解、多模态生成等多种功能截至今年3月,该软件的用户已突破2.13亿,数据2.13亿用科学记数法可以表示为A.2.13×107B.21.3×107C.21.3×108D.2.13×108[2x>4,7.不等式组-1≤1的解集在数轴上表示正确的是2012345012345012340123ABC8近几年青少年近视的现象越来越多,为保护视力,A某公司推出一款亮度可调节的台灯.我们知道,导体中的电流I,与导体的电阻R、导体两端的电压UJ之间满足关系式=R,所以台灯灯光亮度的改0.2变,可以通过调节总电阻来控制电流的变化实现。如图是该台灯的电流I(A)与电阻R(2)成反1100R①比例函数的图象.根据图象可知,下列说法正确的是A1与R的函数关系式是I=1100(R>0)RB.当R=500时,=2C.当电阻R(2)越大时,该台灯的电流I(A)也越大D.当500九年级数学试题第2页(共8页)榆次区 2024 年九年级第二次模拟测试题数学参考答案及评分细则一、选择题(本大题共 10 个小题,每小题 3分,共 30 分.)题号 1 2 3 4 5 6 7 8 9 10答案 B B D A C D C D C B二、填空题(本大题共 5个小题,每小题 3分,共 15 分)x 2 3 1511. 12. (2 ,1) 13. 14. y 15. 8 52 4 x三、解答题(本大题共 8个小题,共 75 分.)16.(本题共 2个小题,第 1小题 4分,第二小题 6分,共 10分) 2(1 1)解: 5 4 3 5 2 9 ······························································3分 2 ···································································· 4分2x x(2) 1x2 1 x 1 2x x解:原方程可化为 1(x 1)(x 1) x 1 ························5分方程两边同时乘 (x 1)(x 1) 得,2x x(x 1) (x 1)(x 1). ···························· 7分1解,得x .3 ························································9分1检验:当 x 3时,(x 1)(x 1) 0.1所以原方程的解是x . ····································· 10分317. (本题 6分)解:设 2023年该村村集体增收为 x 万元,劳务增收为 y 万元.···························································· 1分 x y 180,根据题意,得 60%x 50%y 100. ·····················3分 x 100,解,得 ···························································5分 y 80.答:2023年该村村集体增收为 100万元,劳务增收为 80万元.···6分18. (本题 10分)(1)50 ; ··········································································· 2分1(2)············································································· 4分(3)80;·············································································· 6分(4)答案不唯一,选择两个方面言之有理即可.(每个方面 2分)例如:从平均分看,因为小红同学的成绩为 80分,等于现在总体成绩的平均分,所以加入小红的成绩后,九(1)班总体成绩的平均分不变.从众数看,因为加入小红成绩之前,九(1)班总体成绩的众数为 80分,小红同学的成绩也为 80分,所以加入小红的成绩后,九(1)班总体成绩的众数不变.从中位数看,因为加入小红成绩之前,九(1)班总体成绩的中位数为 80分,加入小红的成绩后,九(1)班总体成绩的中位数仍为 80分,所以加入小红同学的成绩后,九(1)班的总体成绩的中位数不会发生变化.从方差看,因为小红同学的成绩为 80 分,等于现在总体成绩的平均分,加入小红成绩之后,根据方差公式,九(1)班总体成绩的方差会变小.19. (本题 8分)解:如图,延长 EF,与直线 AB,CD 分别交于点 G,H.··················1分由题可得四边形 ACHG 为矩形,GH=AC= 9 m,AG=CH=50 m.在 Rt△CHF 中,∠CHF=90°,∠FCH=25°,CH=50 m.tan FCH= FH∴ ∠ .CH∴FH CH ·tan∠FCH≈23.5(m),·······4分在 Rt△EAG 中,∠AGE=90°,∠EAG=20°,AG=50 m.EG∴tan∠EAG= .AG∴ EG AG ·tan∠EAG≈18(m).·········································· 7分∴EF=EG+GH-FH≈3.5 (m).∴该电子屏 EF 的高度约为 3.5 m.············································· 8分220. (本题 9分)解:(1)A(-3,0),B(1,0),C(0,3);································· 3分(2)如图,过点 P 作 PE⊥x 轴,交 DB 于点 F,交 x 轴于点 E. 过点 D作 DQ⊥PE 于点 Q.∵点 D 为点 C 关于抛物线对称轴的对称点,C(0,3),抛物线对称轴为直线 x 1 .∴D(-2,3).································4分设直线 BD 的函数表达式为 y = kx+b.将 B(1,0),D(-2,3)分别代入 y = kx+b, 0 k b, k -1,得 解,得 3 -2k b. b 1.∴直线 BD 的函数表达式为 y x 1.······ ······················· 5分设点 P 的坐标为(m, m 2 2m 3),∴点 F 的坐标为(m,-m+1).∵点 P 为直线 DB 上方抛物线上一动点,∴ -2∴PF=( m2 2m 3)-(-m+1)= m2 m 2 .··············6分S 1 △PDB S△PFD S△PFB PF (DQ BE)21 ( m 2 m 2) (x2 B xD )3 (m 1)2 27 .2 2 8··············································· ······························· 7分3∵ 0 1,∴当m 时,△PDB 的面积最大.············ 8分2 21 15此时点 P 的坐标为( , ).······································ 9分2 421.(本题 9分)解:(1)对角线互相平分的四边形是平行四边形;· ·····2分AO AD(2)∴ .····································· ·····3分OG DB∵CD 是△ABC 中 AB 边上的中线,∴AD=DB.3∴OA=OG.··························································································4分∵OE EG, ∴OG=2OE.∴OA=2OE.···························································· ····························5分方法二:∴∠ADO=∠ABG,∠AOD=∠AGB. ∴△ADO∽△ABG.AO AD∴ .··········································· ·········· ·········· 3分AG AB∵CD 是△ABC 中 AB 边上的中线,∴AB=2AD.∴AG=2AO. ∴OA=OG.································ ····························4分∵OE EG, ∴OG=2OE.∴OA=2OE.···························································· ····························5分(3)···························································· 7分2. ·············································································· 9分22.(本题 11分)解:任务一:120÷5=24,24÷2=12,∴顶点 A 的坐标为(12,-24), B(24,0)························ 2分∴设抛物线模具的函数表达式为 y a(x 12)2 24,·················· 4分1将 B(24,0)代入 y a(x 12)2 24,解得 a . ················· 5分61所以抛物线模具的函数表达式为 y (x 12)2 24 1,即 y x 2 4x.6 6····························································6分方法二:120÷5=24,24÷2=12,∴顶点 A 的坐标为(12,-24), B(24,0)························ 2分∴设抛物线模具的函数表达式为 y ax 2 bx ,························· 3分4将 A(12,-24),B(24,0)代入 y ax 2 bx , 24 122 a 12b 1, a ,得 解,得 6 0 242 a 24b. b 4.························ 5分1所以抛物线模具的函数表达式为 y x 2 4x.6 ···························6分方法三:120÷5=24,24÷2=12,∴顶点 A 的坐标为(12,-24), B(24,0)························ 2分∴设抛物线模具的函数表达式为 y ax(x 24),······················· 4分将 A(12,-24)代入 y ax(x 24) 1,解,得 a . ··············· 5分61 1所以抛物线模具的函数表达式为 y x(x 24) x 2 4x. ·············6分6 6任务二:(24-12)÷2=6,-24+6=-18············································ 7分将 y=-18 1代入抛物线解析式 y (x 12)2 24得: 18 1 (x 12)2 24,6 6解,得 x1 18, x2 6.·························································9分 x1 x2 18 6 12. ························································· 10分120÷12=10(个).答:方案二的一排中最多可摆放 10个花边.···························· 11分23.(本题 12分)解:(1)在正方形 ABCD 中,∴AD=AB,∠BAD=90°.···· 1分由旋转得 AH=AG,∠GAH=90°.···················2分 2分∴∠BAD-∠GAF=∠GAH-∠GAF.∴∠BAG=∠DAH.······································ 3分∴△BAG≌△DAH(SAS).··························4分图 1∴GB=HD.················································ 5分(2)四边形 AGFH 为正方形.································6分5证明:∵点 E,F 分别是边 AB,AD 的中点,AD=AB,∴AE=AF.∵在等腰 Rt△AEF 中,点 G 是 EF 的中点,1∴AG⊥EF,AG= EF=GF.····································8分2∴∠AGF=90°. 图 2∴AH∥GF,AH=GF.∴四边形 AGFH 为平行四边形.······················9分∵∠GAH=90°,AG=AH,∴□AGFH 为正方形.································ 10分( 3 )16 或8 4 2 . ·········································12分5备注:15题解法分析:6 展开更多...... 收起↑ 资源列表 山西省晋中市榆次区2024年九年级二模数学试卷(PDF版,含答案).pdf 数学答案.pdf