2021-2022学年浙江省绍兴市诸暨市八年级（上）期中数学试卷（附答案详解）

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ਭᵨ2021-2022
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422.(Z(⚪6.0ᑖ)᝞NOCrAEḄ=DC1AE,DC=AC,BCD=S.AB=DE.(1)lcsAABCDEC(2):4=20஺l4EḄTᦪ.23.(Z(⚪6.0ᑖ)᝞A/ICBJ!ECDtuῪ:4cB=NECD=90஺஺AB=DE4cw$AB=17.পlcs^BCD^^ACE.(2)8஺=5,lDEḄ.24.(Z(⚪6.0ᑖ)᝞ᙠ5x5Ḅz{1(Ḅt
1,|ᙠᡠ~z{VW☢⚪.(1)r4BḄtEᙠ{(ᓽ(Ḅ⚔)l.4BḄT(2)0AB
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¶·uῪ!4BC,CD4c=BC=1AB.(1)᝞2,7AB=108lcsCDLAB-,(2)7ABC஺0BC
ῪḄuῪ8lBCḄ(3)74B>58ᙠrBCᔲºᙠE,CDABDEJ!ACDᐰuºᙠl.BCḄ½ºᙠ|abᳮᵫ(4)·4ᐵ%CDḄÀÁ4',ÂÃCA'7C47/4B8CA'=(|ᑏ.Wᫀ).

6

7WᫀV᪆1.ூWᫀ௃BூV᪆௃Vs4ஹ½ÉÀÁᦑZ⌱⚗½ᔠ⚪Í8ஹÉÀÁᦑZ⌱⚗ᔠ⚪ÍCஹ½ÉÀÁᦑZ⌱⚗½ᔠ⚪Í஺ஹ½ÉÀÁᦑZ⌱⚗½ᔠ⚪Í.ᦑ⌱sB.᪷ÏÉÀÁḄᭆÑÀᔜ⌱⚗ᑖ᪆ᑨÔᓽÕDV.Z⚪ὃ×ØÉÀÁḄᭆÑÉÀÁḄᐵÙÚÛÀÁÉHᑖᢚBÜÕÝᔠ.2.ூWᫀ௃BூV᪆௃VsA⌱⚗3+4=7<8,Þ(%ᦑ½ßàᡂ8⌱⚗5+6=11>10,10-5<6,Þᜧ%Þ(%ᦑßàᡂC⌱⚗5+5=10<11,Þ(%ᦑ½ßàᡂ஺⌱⚗5+6=11,Þ½ᜧ%ᦑ½ßàᡂᦑ⌱sB.᪷ÏḄᐵâᓽÕlã⚪ä⌕ὃ×Ḅᐵâ⌕æçèéêḄᐵâsᙠ=ëÍÞᜧ%ëÍÞ(%.3.ூWᫀ௃CூV᪆௃Vsab¤⚪“M>4,ᑣx>2”Ꮇ¤⚪Ḅ=ìíÕ0x=-3.ᦑ⌱sC.7î==38ïð/>4,ñ½ßDᑮx>2,%x=-3Õ·
ab¤⚪“/>4,ᑣ>2"Ꮇ¤⚪Ḅ=ìí.Z⚪ὃ×ؤ⚪JᳮsᑨÔ=óôḄõö¤⚪.÷ø¤⚪tᵫ⚪ùÃúHᑖà

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AA+Z.B+Z.C=180°,24=180°,••.NA=90஺ᓽHABC_OVOᦑX⌱⚗Rqᔠ⚪sK஺ஹa
b
c=12:13:5a=12k,b=13k,c=5k,■■■(5fc)2+(12/c)2=(13k)2,

9
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Z,OAD=OCE=60°,.•.4EÝ4BḄᜳOê60஺ᦑঝvBED-Z.AED=Z.AEB

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Z-C—Z-B=22°,•
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14.uEFGuGMH(44S),FG=MH=7,GM=EF=5,EF2=52=25,HM2=72=49,hqBḄ☢EG?=EF2+FG2=EF2+HM2=25+49=74,ᦑᫀ74.v^EFGwAGM”,xaFG=MH=7,GM=EF=5,yijEF?=25,HM2=49,@vEG?=EF2+FG2=EF2+“M2,zᐭ`aᓽ%.&⚪ὃ(IᐰḄᑨdBឋ=ஹhqḄឋ=[~KLhqḄឋ=vuEFGAGMH)#⚪ḄᐵJ.16.ூᫀ௃2ூ#᪆௃#VAB=AC,AB=4,
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.ZC=4CBE=30°,

169A=Z.ABD=15°.
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Z-BDC=Z-A+Z-ABD=30°,BEA=Z.C+CBE=60°.


EBD=90°.ᙠt


ED=2,Z,BDC=30°,•••BE=1,BD=V3.ACE—BE,AD—BD.■■■AC=CE+AD+ED=1+2+yf3=3+^3.ᦑᫀ3+ᑭᵨ¥ᚖᑖḄឋ=¾ABCEXAADB)Ὺ@ᑭᵨῪḄឋ=`aNBE4XNBDCḄbᦪᑭᵨᱯÀḄḄឋ=`aBEஹDBḄrᨬ-ᑭᵨ¥ḄXÁᐵE>23.&⚪ὃ(Ḅ)Ḅឋ=ஹ¥ᚖᑖḄឋ=ஹῪḄឋ=KLᙠt30஺ᡠMḄ__Ḅ)#⚪ḄᐵJ.20.ூᫀ௃45஺ᡈ30஺ூ#᪆௃#UD47/BC,᝞o^A'DA=AACB=90°,.•■u4OEÂCEᢚÄᑮAOE,^ADE=^A'DE=-/.ADA'=45°,UE47/BC,᝞oÅ.44',

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4C=BC,EC=DC,Z.ACB=LECD=90°,
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19•••ABC)Ὺ/.CAB=4CBA=/.CAE=45°,•••/LEAD=45°+45°=90°,ᙠRt^AOEtᵫÙÚdᳮ>DE=yjAD2+AE2=V122+52=13.ூ#᪆௃(1)᪷S4SvAACEBCD,ᓽ%ফᵫᐰḄឋ=>“AE=஻BD,AE=BD=5,v>NEAD=90஺᪷ÙÚdᳮ%>a23.&⚪ὃ(IᐰḄᑨdXឋ=ஹÙÚdᳮஹῪḄឋ=[~#⚪ḄᐵJ)hiÜÝᐰ#Èg⚪.24.ூᫀ௃#(1)ᵫÙÚdᳮ᧕[48=ß(2)⌕ÑA/BCῪàá_rbᙳãᳮᦪজå4BV_ᑣ⚔ᙠ¥48Ḅtᚖ᧕[QRSæᡂç.ᦑA8_NῪ.ঝå4BῪéêë%[ᨵCìᩩ°F,BCḄrbãᳮᦪ᝞íoᡠî:(3)6.ூ#᪆௃(1)ᵫ⚪Ê4BḄ_ᦑ48=112+22=▲(2)Fm⚪⌕`ðñMg⚪ᑖRSn3A8ῪAB_VQRS.(3)4B_Ὺᙠò_ᨵ%óÝaô_ᨵ4
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20
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21
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