2020-2021年重慶市潼南區(qū)八年下末數(shù)學(xué)試卷一、選擇題本大題共12個小題，每小題4分共48分）在每個小題的下面，都給出了代號為、B、D的四個答案，其中有一個是正確的，請用B鉛筆將答題卡上對應(yīng)題目右側(cè)正確答案所在的方框涂黑A3

B3CxA13B815C13D1020ABCDAC

BD23A

B3

C

D6/30

A7

B8

C8.5A5

B67

C7

D8AEAEBCE70A10

B15

C20

D30AB2000CD/10ABCDPQCB20A116.5

C7D7.5x++m/30

2222A0B2CD512EFBCBACBEPPDmA64B84CD6+4二、填空題（本大題共6小題，每小題4，共24分）請將每個小題的答案填在答題卡中對應(yīng)的橫線上13

14x1551360cm

16317ABCDADEFEFABACDBC157DH181590A610A110/30

三、解答題（本大題共7個小題，每小題10，共70）解答時每小題必須給出必要的演算過程或推理步驟，請將解答過程書寫在答題卡中對應(yīng)的位置上①

+

②

AD1ACBCMDAEBD2FAD4BC/30

1010x5xx5xD79ABx5C

D

5.4m

4.5

t1n23/30

31xyx1yxy

2m

1

m2①②30alxlx1|

/30

2228/

//

//1210aw2cd

a64534566453345612

/30

2EADPBCPDDPE1PEAF①DP②FADAF2PFDP2FAD2AFPF/30

1212四、解答題1小題，滿分）請將解答過程書寫在答題卡中對應(yīng)的位置上lyxyClx12DOACD3PCDQOPQP/30

222222222222222222參考答案與試題解析一選題共12?。〢3

B3Cx0x0x3DA13B815C13D10203B

+13

CDCABCD根①②③④ADC10/

AC

BD解23A

B3

C

D6根2ykx3kkyCCA7B8CD95+15+18+723239911/

D

A5

B67

C7

D84

5

7AEAEBCE70A10

B15

C20

D30AEDCEDEAD70EADADECDEEBCADCDDEDEAEDCEDEADECDBECBEC+6545+ECD20EAD20C12/

菱形菱形AB2000CD/10510ABCDPQCB20A116.5D7.5BC5eq\o\ac(△,Rt)QEC3PEPQ2SABCDBPPQPQEC520eq\o\ac(△,Rt)EQ13/

BCEPBCEP2535+241411陰影正方形梯形x

+

2++2mA0B2CD5+mxmyxm+2m+2m2x

+

2xm2m21023212EFBCBACBEPPDmA64B84CD6+4EHDACPDBEEHeq\o\ac(△,Rt)HCE45HCEH2xEHxx214/

222222222eq\o\ac(△,Rt)BCF

8

m

EHHDACPDBFEHABEAHE90eq\o\ac(△,Rt)ABEeq\o\ac(△,Rt)AHeq\o\ac(△,Rt)EHCHCE45HCEHBExEHHC2xCFCF2eq\o\ac(△,Rt)BCFBF84

84

二填題共小題13

15/

222222222714xyxb2xy21yx11551360cm120cm512x5+12+1360x10cm10261016314或ABEBE33，ADBCDAEDAEBAE16/

BE①ABBEcmCE14②3cm2cm16141617ABCDADEFEFABACDBC157DH

EFABA'B2BEEA30ABG14

BEAFHFDH2

ADEFEF'BB2BEeq\o\ac(△,Rt)'B60ABG'ABG17/30

AGBG

E

B7

AD15F15HA'30HF2

2

181590A610A11012B10an①②ba③bnmnnmb9nm1a+9①a12B1218/

12三解題①

+

②

①4+

②114

①②①4+2②9116+2114

+2AD1ACBCMDAEBD2FAD4BC219/

2AE3BCFBCDE2CMACBBCEACEADBCAECBCEACEAECBDBCFDEFBCFDE1010x5xx5xD79ABx5C20/30

D

5.4m

4.5

t1n23用43192010t10n23521/

5104105n55433200531xyx1yxy

2m

1

m2①22/

②30alx

lx1|4x+2①②1y1|3xmn2①x②133l1ax4x13+x1x+2x1yxx+2x2mx3xx+212①1y31|23/

②3xy31|xy31|33lxll3lxa8/

//

//1210aw224/

)8270+114000a35182w3962wx2a1010aw+800+500a10a]70a0a3a+8a0838w70ak0aW25/30

22222222222222222W3+11400711610cd

a64534566453345612

54142

456264533456

a+61a24575414253525+1641412a+61

26/30

66152EADPBCPDDPE1PEAF①DP②FADAF2PFDP2FAD2AFPF正②52PDAF+GAEDPE②＝GF72GFPGFGPDPDGAEPDEGDPEDEAEGAASAGDP②DPEDPE27/

1212GGFPF2AGAGDPDP2PDAF+PF2PDGDPEGFGAEGAEDEAEGAASAGPDAGAFPDAFlyxyClx12DOACD28/

11111111122333PCDQOPQP2DDCODxCD3PCDOQC90OPCOPPCP632DxCOD12xx4D2+042

29/