2021-2022学年江苏省无锡市江阴市澄要片八年级(上)期中数学试卷

△△学年江省无锡市阴市澄要八年级第学期期中数学试卷一选题本题10小，小3分共分．每题给的个项，只一是确，用2B铅笔把题上应选标涂）A

B

C

DA2B22DA101011D711ABCDA4cm6cmC34

B1cmD1.522.5cmASASBDABCDEF、Beq\o\ac(△,)ABCAACDFBDCDFDACBFADBACBCDEDFF12

DFACA2B4CD9ABCABACDEABBEACAFA35

B40

C45

D6010BCBDDEFACFCDFA3B2CD4二填题本题8小题每题3分，分不写解过，需把案接写答卡相的置111211013eq\o\ac(△,Rt)ABC903D14ACBeq\o\ac(△,A)eq\o\ac(△,)CB70B

1522116

21

17AC8PQACAAXPQABAPABCPQA

18AC4ADBACBCD20三解题本题小，66分请答卡指区内答解时写文说、明程演步）19DBODCABO1DCO2OBC35OCB20ACMN1eq\o\ac(△,A)eq\o\ac(△,)BC231ABC

21eq\o\ac(△,Rt)901291AE222ABCDcm4EFD1BF2BEF23ACB90DBCDEABEADEFCF123024ABCDABC1BD21ABCDBD

251AB23ABCD90ECDABCDAACExy11yx5.5y2PBC3PPPAD26ABCDADBAD120EBCCDEAFBEFDFDGBEADGAGFABCDEBCAEBCAEF90①BE+DQ②PHPH

参考答案一选题本题10小，小3分共分．每题给的个项，只一是确，用2B铅笔把题上应选标涂）A

B

C

DABCDA2B22D4CA101011D7114①343+3+410②33+443+4+411

ABCDCA4cm6cmC34

B1cmD1.522.5cm42

A3B

+3

C1.5

2

+22

DDASASBDDDABCDEF、Beq\o\ac(△,)ABC

ABDABDAACDFBDCDFDACBFDEDEFDFACBFDEFADDASADEFBSSAABCCADBACBCDEDFF12DFACA2B4CD9BACDEDFDEDF2S+12AB+ACDF24AB2+39DABCABACDEABBEACAFA35

B40

C45

D60

BEABEABCABBCBFCFBFBEABEBAC45ABC180CBEABCABE67.522.5CFCBE22.5EFCCBE22.545C10BCBDDEFACFCDFA3B2CD4DBCFHHDMFHGEEHGH2

DDGBCFHBCHDMFHMBDDEDMBCBGEHGE+EH22FHDGBCDMH90DGHMGH2DFDMDF二填题本题8小题每题3分，分不写解过，需把案接写答卡相的置11FMFM379FM12110①2②24035

13eq\o\ac(△,Rt)ABC903D2.5ABC905DABCD14ACBeq\o\ac(△,A)eq\o\ac(△,)CB70BACBeq\o\ac(△,A)eq\o\ac(△,)'BB707015221+5+21a2a+51+59

16

1eq\o\ac(△,Rt)ABCAB2C90BCmm108

17AC8PQACAPQABAP38ABCPQA①PCAP8QAP②APPAQ①PC8BCAQAPeq\o\ac(△,Rt)BCAeq\o\ac(△,Rt)②BCAeq\o\ac(△,Rt)BCAeq\o\ac(△,Rt)PAQ18AC4ADBACBCD2010CDEADEADCASAACAEDECDBEBC

BDCBECBDCBDCBECBDC公式即可得到答案．解：如图：延长AB，于点∵AD平BAC∴∠＝EAD∵CD⊥，∴∠＝ADE＝，在△和△ADC，，∴△≌△ADC（ASA）∴ACAEDE＝CD；∵ACAB＝，∴AEAB4，即BE＝；∵DE＝DC，∴SS，∴当BE⊥BC时，S最＝，∴BEBC＝∴BC＝．故答案为10

4BC＝，三解题本题8小，66分．在题卡定域作，答应出字说、明程演步）19．知：如图AC、DB相于AB＝DC，∠ABO＝∠DCO．

1DCO2OBC35OCBAASDCO2OC1ABOAAS2ABOOBOCOCB20ACMN1eq\o\ac(△,A)eq\o\ac(△,)BC231ABC3ABC231eq\o\ac(△,A)eq\o\ac(△,)'B'C'

23221eq\o\ac(△,Rt)901291AE2ABMN2AEx1E2AExMNAExeq\o\ac(△,Rt)ECBEC+2212

+922

x

AE

△BE△BE22ABCDcm4EFD1BF2BEFBEFDEFx8BEDEFADBCBF2AEBEDE8eq\o\ac(△,Rt)2+428x2x3BFAB23ACB90DBCDEABEADEFCF1230

ADCFADEFCF2EFAFCFFEAFCAFACEFCEFCDEDEA90ACBACDeq\o\ac(△,Rt)AEDeq\o\ac(△,Rt)FADCFADCF2EFCCEeq\o\ac(△,Rt)AEDeq\o\ac(△,Rt)FCFADFCAFACEFCEFDCFD2FAC2BACEFC2BAC60CFEFC24ABCDABC1BD

21ABCDBDEACAND90BD2DEBDBCABC45BCABDAEBMCAEBD2DEACEACBCDDEADEADC+CDE903BD

251AB23ABCD90ECDABCDAACExy11y5.5y2PBC3PPPADx1PABx5.5PCD23P1xPAB1yAPBC1x5.5CEAB+BC+5.5y2PBCy32x25x1yx5EC''CECBCAPE

'12DEADDEDAEPAD4526ABCDADBAD120EBCCDEAFBEFDFDGBEADGAGF

EFBE+FDABCDEBCAEBCAEF90①BE+DQ②PHPHFDGDGAGADGAEFGDGABEADGAGQG3QEP

1EF+FDA