2026年5月山西省大同市部分学校中考二模九年级数学试卷(扫描版,含答案)

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2026年5月山西省大同市部分学校中考二模九年级数学试卷(扫描版,含答案)

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5.在一个不透明的袋子中装有两个红球,一个白球,一个黄球,这些球除颜色外都相
同.从中一次摸出两个球,记下颜色后放回,多次重复上述试验,摸到的两个球颜色
相同的频率最可能接近的数值为
A.1.2
B.0.78
C.0.52
D.0.17


6.下面解分式方程1-x=
2
x-3=3-
一的步骤中,错误的是
A.将方程两边同时乘x-3可转化为整式方程
注意事项:
B.去分母后的一元一次方程为1-x=-2
1.本试卷共8页,满分120分,考试时间120分钟.
C.原分式方程的解为x=3
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
D.原分式方程无解
3.答案全部在答题卡上完成,答在本试卷上无效
7.开窗见蓝天、出门迎白云,如今已成为太原市民的日常.一组数据印证了这份“蓝天
4.考试结束后,将本试卷和答题卡一并交回
幸福感”:2023年全年太原市空气污染天数为121天,2025年全年太原市空气污染
天数为82天.设连续两年太原市空气污染天数的平均减少率为x,则下面所列方程
第I卷选择题(共30分)
正确的是
A.121(1-x)2=82
B.121(1-x%)2=82
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,
C.82(1+x)2=121
D.121(1-2x)=82
只有一项符合题目要求,请选出并在答题卡上将该项涂黑)
1.二十四节气是中国古代农耕文明的重要组成部分,用来指导农业生产和日常生活
8.如图,E,F是口ABCD中DA,BC延长线上的两点,连接EF分别
乐乐查询了当地2025年大寒时的最高气温为-7℃,大暑时的最高气温为30℃,则
交AB,CD于点G,H.下列各式中正确的是
两个节气的最高气温相差
AC剧
B.
EG BC
GH AE
A.37℃
B.33℃
C.30℃
D.23℃
DH AG
第8题图
2.山西省,简称“晋”,又称“三晋”.下面是小明收集的关于“晋”字的演变过程,其文字
c治-所
D.
CH=BG
上方的部分是轴对称图形的是
9.已知点A,B是一次函数y=-mx+n(m≠0)图象上的两点,若y,
确的是
A.xB.>x
C.x1=x习
D.无法判断
甲骨文
金文
小篆
楷书
10.如图,AB是⊙0的直径,AD,BC,AC是⊙0的弦.若∠BAD=30°,
A
B
D
BD=BC,AC=3√3,则AC长为
3.下列运算正确的是
3
A.xx=x
B.(x-1)(x-1)=x2+1
A.2T
B.2T
C.(-m2)3=-m6
D.m2+m'=m
C.√3m
D.3√3T
第10题图
4.位于朔州市的应县木塔,是“世界三大奇塔”之一,也
第Ⅱ卷非选择题(共90分)
是世界上现存最古老的纯木结构楼阁式建筑,它的结
构独特,全榫卯连接,没有一根铁钉.右图是一种简单
二、填空题(本大题共5个小题,每小题3分,共15分)
A
的榫卯结构示意图,几何体A和B组合后得到新的几
正面
11.比较大小:√5▲2(填“>”“=”或“<”).
何体,其中几何体A的俯视图为
第4题图
12.如图,△ABC的顶点B,C的坐标分别为(1,-1),(2,1),将
△ABC沿CB方向平移得到△DEB,若点A的对应点D的坐
B
标是(-2,0),则点A的坐标为▲
第12题图
数学试卷(二)第1页(共8页)
数学试卷(二)第2页(共8页)数学参考答案与评分标准
一、选择题
1 2 3 4 5 6 7 8 9 10
A C C B D C A A B B
二、填空题
11. > 12. (-1,2) 13. 9 14. 100
15. 2
提示:如图,连接 BG,过点 G 作 GM⊥BC 于点 M,过点 G 作 GN⊥DC,交
DC的延长线于点 N.
∵EF垂直平分 BD,∴BG=DG.∴∠DBG=∠BDG=45°.
∴∠GDN+∠ADB=90°-∠BDG=45°.
由矩形易得∠ADB=∠DBC,
∵∠GBM=45°-∠DBC,∠GDN=45°-∠ADB,
∴∠GDN=∠GBM.
∵BG=DG,∠BMG=∠DNG=90°,
∴△BMG≌△DNG.∴GM=GN,BM=DN.
易证四边形MGNC是正方形,设正方形边长为 x,
则 BM=4-x,DN=2+x.∴4-x=2+x.解得 x=1.∴CG= 2 .
三、解答题
16.解:
(1)原式=-3-9+(-2)································································································· 3分
=-14.················································································································ 5分
2 = a 1 a 1
2
( )原式 ·······························································································7分
a a a 1
a 1 a a 1= 2 ·······························································································8分a a 1
=1.···················································································································· 10分
17.证明:∵CE⊥AD,DF⊥BC,
∴∠CED=90°,∠F=90°.·························································································1分
∵四边形 ABCD是平行四边形,
∴AD∥BC.··············································································································· 2分
∴∠ECF+∠CED=180°.
∴∠ECF=90°.··········································································································· 3分
∴四边形 CEDF是矩形.·························································································· 4分
∵∠ADC=45°,
∴∠ECD=90°-45°=45°.··························································································· 5分
∴∠ADC=∠ECD.
∴DE=CE.··················································································································6分
∴矩形 CEDF是正方形.·························································································· 7分
18.解:(1)设单目显微镜的单价为 x元/台,双目显微镜的单价为 y元/台.··········· 1分
3x 2y=1440,
根据题意,得 ··················································································3分
8x 5y=3720.
x=240,
解,得 ·········································································································4分
y=360.
答:单目显微镜的单价为 240元/台,双目显微镜的单价为 360元/台.················ 5分
(2)设可购买双目显微镜 m台.
根据题意,得 240(30-m)+360m≤10 000.·····························································6分
解,得 m 70≤ .
3
因为 m为整数,且 m取最大值,所以 m=23.··························································7分
答:最多可购买双目显微镜 23台.·············································································8分
19.解:(1)①C················································································································1分
③D·····························································································································2分
④88.8·························································································································3分
(2)补充完整的统计图,如图所示:······································································5分
20 6
(3)600 =312(名).
50
答:估计有 312名学生能完成目标.·······································································6分
目标合理.
理由:因为 40%+12%=52%,过半的学生都能完成这个目标,所以这个目标
合理.···························································································································7分
(4)①学校“阳光体育运动”采取的措施成果显著,超过一半的学生平均每天
体育运动的时间为 90分钟;②仍然有 18%学生每天平均体育运动的时间不
足一小时,学校还需提供更多的体育运动机会.(合理即可)···························9分
20.解:如图 1,延长 DE交 AB于点M;如图 2,延长 PQ交 AB于点 N.············· 1分
图 1 图 2
则四边形 DCBM,四边形 PCBN都是矩形.
∴BM=DC=1.5 m,BN=CP=10.5 m,DM=PN=BC.
设 AB=x m,则 AM=(x-1.5)m,AN=(x-10.5)m.········································2分
在 Rt△ADM中,∠AMD=90°,∠ADM=50°,
∴tan∠ADM= AM .
DM
DM= AM x 1.5∴ .··················································································· 3分
tan ADM 1.19
在 Rt△APN中,∠ANP=90°,∠APN=37°,
∴tan∠APN= AN ,
PN
PN= AN x 10.5∴ .·················································································· 5分
tan APN 0.75
x 1.5 x 10.5
由 DM=PN,得 .
1.19 0.75
解,得 x≈25.8.·········································································································· 6分
答:城门顶部点 A到地面的距离 AB的长约为 25.8米.····································· 7分
21.解:(1)∵∠BCD=∠AFE,
∴180°-∠BCD=180°-∠AFE.
∴∠3=∠4.················································································································ 1分
∵∠H=180°-∠3-∠2,∠G=180°-∠4-∠1,
∴∠H=∠G.·············································································································· 2分
∵∠ABC=∠DEF,
∴∠H+∠ABC=∠G+∠DEF.·················································································· 3分
∵∠H+∠ABC+∠G+∠DEF=360°,
∴∠H+∠ABC=180°.······························································································· 4分
∴BG∥HE,
即 AB∥DE.···············································································································5分
同理可得 BC∥EF,CD∥AF.
∴凸六边形 ABCDEF是平行六边形.·····································································6分
(2)是 ····················································································································7分
(3)如图,六边形 AEFCGH即为所求.
··················································································9分
22.解:(1)∵线段 AB和线段 CD互相垂直平分,且 AB=CD=6,
∴A(-3,3),B(3,3),C(0,6).································································ 1分
由已知,点 C为抛物线的顶点,
∴设抛物线的函数表达式为 y=ax2+6.····································································2分
将 A(-3,3)代入,得 9a+6=3.
解,得 a= 1 .··········································································································· 3分
3
1
∴抛物线的函数表达式为 y x2 6 .································································ 4分
3
: 2 y=0 1( )当 时, x2 6 0.
3
解,得 x1 3 2,x 2 3 2. ·····················································································5分
∴ E( 3 2,0), F (3 2,0).
∴EF 6 2 cm.······································································································6分
由已知,得点 G和点 H的纵坐标为 4.
1
当 y=4时, x2 6 4.
3
解,得 x1 6,x 2 6. ························································································ 7分
∴G( 6,0),H ( 6,0).
∴GH 2 6 cm.·····································································································8分
3 2 4 17( )① n m2 m . ·················································································10分
3 3 3
8 5
②窗框的总长度为 (4 ) cm. ·················································································12分
5
23.解:(1)四边形 CDGF是菱形.·················································································1分
理由如下:由旋转得∠DCF=120°,∠F=∠BDC=60°,DC=FC,
∴∠DCF+∠F=180°.
∴DC∥GF.················································································································ 2分
∵∠DBC=90°,
∴∠BCD=90°-∠BDC=30°.
∵△ABC是等边三角形,
∴∠ACB=60°,AC=BC.
∴∠ACD=∠ACB - ∠BCD=30°.
∴∠ACD=∠BCD.
∵CD=CD,
∴△ACD≌△BCD.··································································································3分
∴∠ADC=∠BDC=60°.
∴∠ADC+∠DCF=180°.
∴DG∥CF.
∴四边形 CDGF是平行四边形.··············································································4分
∵DC=FC,
∴四边形 CDGF是菱形.··························································································5分
(2)AD=EG.理由如下:
如图 1,延长 DC到M,使 DM=DB,连接 BM,CG.
图 1
∵∠BDM=60°,
∴△DBM是等边三角形.···························································································· 6分
∴∠DBM=∠M=60°,BD=BM.
∵△ABC是等边三角形,
∴∠ACB=∠ABC=60°,AB=BC.
∴∠ABC - ∠DBC=∠DBM -∠DBC.
∴∠ABD=∠CBM.
∴△ABD≌△CBM.····································································································· 7分
∴∠ADB=∠M=60°.
∵∠BDC=60°,
∴∠CDG=180°-60°-60°=60°.
由旋转得∠DCF=120°,∠F=∠BDC=60°,CD=CF,
∴∠DCF+∠F=180°,∠DCF+∠CDG=180°.
∴CF∥DG,CD∥GF.
∴四边形 CDGF是平行四边形.··················································································8分
∵CD=CF,
∴四边形 CDGF是菱形.
∴DC=DG.
∴△DCG是等边三角形.····························································································· 9分
∴DC=GC,∠DCG=60°.
由旋转得∠BCE=120°,AC=EC,
∵∠ACB=60°,
∴∠ACE=60°.
∴∠ACE-∠DCE=∠DCG-∠DCE,即∠ACD=∠ECG.
∴△ACD≌△ECG.
∴AD=EG.····················································································································· 10分
(3 1 1) 或 .······················································································································13分
2
(答对 1个 2分)
提示:分∠DCH=90°和∠DHC=90°两种情况讨论.
情况一:当∠DCH=90°时,如图 2,∠ECF=∠DCF-∠DCH=30°.
∵四边形 CDGF是菱形,∴GF∥DC.∴∠FEC=∠DCH=90°.
∴EF= 1 FC. EF= 1 GF. EG=EF. EG∴ ∴ ∴ =1.
2 2 EF
图 2 图 3
情况二:当∠DHC=90°时,如图 3,∠DCH=90°-∠CDH=30°.
1
∴DH= DC.∴DH= 1 DG,DH= 1 CF.∴DH=HG,HG= 1 CF.
2 2 2 2
∵四边形 CDGF是菱形,∴DG∥CF.∴△EHG∽△ECF. EG = HG 1∴ .
EF CF 2
EG 1
综上所述, 的值为 1或 .
EF 2
【说明】以上各题的其他解法,请参照此标准评分.

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