2021-2022学年四川省成都市新都区八年级下学期期末试卷数学

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2021-2022
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20•e4BC^¯Îº°(2)᝞d1,ᔣÐmntÑᓫÓ-•4E'B'D’ÔaABCÕÖ×ᑖḄd°¬Ø¯°,•FH),AHJK,eFG/Ù^¬Åº°,FJ=GJ,/.GF]=^LFG]=60°,vFG1xÊ-FJB=30°,vAABO=30°,:,BF=FJ,:.BF=FH=HK,¬Åº°-•AH=FH=BF,:.t=4,-mnÚÛ4(3)᝞d2,(MhÔ8hÕᔠ,vZ.AMN=60°,½4BC=60஺-NhÔChÕᔠ-N(0,8)-(NhᙠxÊÝ,-,AM=MN,Z.AMN=60°,£.ABO=30°,•/,BAM=30°,•Z,AMO=30°,/.MO=1,AM=2,NO=1,•N(l,0),NᡠᙠḄÞ³᪆y=kx+b,Cfc4-b=0'''lb=-V3'ß-/vs)•y=V3x

21ூ᪆௃(1)XuChᙶ᪗-GᑖsXu4B=4C=BC=2V5,ᓽAᑨâź°Ḅ°ã;(2)ᔣÐmntÑᓫÓ-ᵫ⚪AzeFHJ,HJK,^FG/Ù^¬Åº°-ᑣBF=FH=HK,Gᵫe4HK¬Åº°-ABAH=FH=BF,ÇXumnÚÛ4(3)(MhÔ8hÕᔠ,-NhÔChÕᔠ-ᓽN(0,-b)-(NhᙠxÊÝ,-N(1,O),GᵫᦪðXXuÞ³᪆ᓽA.R⚪^:ñᦪḄÈᔠwᵨ⚪-[\òó:ñᦪḄdôõឋr-¯Åº°Ḅឋr-öᵨᦪðXñᦪḄ᪆^⚪Ḅᐵ`.24.ூBᫀ௃(1)ᵬøᡝ~ú4ûüḄýÙþrªᔴᑣB(100-x)ᔴᡝ4Ḅ(120-x)ᔴB(+30)ᔴᑣy*=18%+20(100-x),ᓽy/=2000-lx.y—15(120—x)+18(x+30),ᓽy=3x+2340(ফᵫ⚪,-./0123-.50<%<86|,789:;<=w,ᑣw=2000-2x+3x+2340=%+5340,v1>0,WBXḄDᜧFDᜧ..♦.Hx=50IwᨬK=50+5340=5390(ᐗ).•••ᵬ9:450ᔴIPQR89:Ḅ;<=ᨬKᨬKS5390ᐗ.ூ3᪆௃(1)7ᵬ9:4WḄXYZᑘ\ᑣB(100-X)ᔴᡝ4Ḅ(120-]ᔴB(x+30)ᔴ᪷_;ᵨabᔴᦪxdᔴḄ;ᵨᓽeᑏghᦪ3᪆i((2)j-xḄlmn;ᵨ⊤pxḄhᦪ᪷_hᦪḄឋj3.r⚪ὃtuvwhᦪḄxᵨjy▭{⚪ḄᨬS{⚪|ᵨḄ}~ᓄhᦪ{⚪,⊤pgᵬᡝ=ᡝ〈ᑮ4=BᔜḄᔴᦪᐵ.25.ூᫀ௃3.(1)EḄᙶ᪗2ᐭyi=—+3,-yi=-2+3=1,••E(2,l),

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