广西南宁市2021-2022学年中考数学模拟试卷（一模）含解析版

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ᫀᓽ"|(4)ᑭᵨ᪛îpÜᑡï²?ᑗ"ñḄò/ᯠeᑭᵨᭆ᳛ó\ᓽ"C.⚪᪆(1)DᔆḄ«¬ãä=1-20%-20%-35%=25%,DᔆḄ«¬ᦪ=2000x25%=500¬|Dᔆ¥ḄᙊÂÃ360'25%=90஺|(2)CᔆḄ«¬ᦪ=2000x20%=400¬/CᔆḄᔠ®«¬ᦪ=400x95%=380¬/᝞pᔠ()800/630ABCDᔆ1(3)Aᔆᔠ®᳛=630+(2000x35%)=90%,Bᔆᔠ®᳛=370+(2000x20%)=92.5%,Cᔆᔠ®᳛=95%,Dᔆᔠ®᳛470+500=94%,ᔠ®᳛᣸ᙠÉ·ÊḄ&CஹD·ᔆ|(4)᪷³⚪!Þ᪛tp᝞úBCJᐳᨵ12©üý/⌱uCஹDḄᨵ2©,21ᑣP(⌱uCஹD)126ὃ
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2.ᡧ3.᪛.22.᝞0ORMABCḄABᑗD,"#AC$EஹF()*DE,+,NB=30஺00Ḅ01212,4DEḄ56247r.(1)<=
DE஻BC?18⚓/C24⚓

18(2)EAF=CE,

19
.OG=-ED=6,2VZA=60°,ED=12,NAED=90°,AD=-ED=8Ssin60°TᡡVsVZFDA=90°,AF=/D-=16'cos60°:•EF=12ᵫ
AF=CE,:CF=AE=B:•CA=AF+FC=20ᵫ5C=ZCtan60°=20^xG=60.23.WXYZ[\ᓬ^⚜ᜓabᵬஹd(eXYf.ᐸhᵬஹd(eXYfḄbijki᝞l⊤.+,ab60nᵬeXYf50ndeXYfᐳᵨ10000ᐗXYfirᵬdbisᐗ/ntmm-20kisᐗ/nt2401601

20(2)¡abᵬeXYfxn⊤£TdeXYf(200-¤nᯠS᪷CᑭyᑡT¦ᐗ~§¨21000©᪷⚪ÇÈv,[(240-100)x+(160-80)(200-x)<22000©,250I~§¨জ%>—3I~§¨ঝx<100,250ᡠÑ~§¨©ḄIªR:Ó<100R᦮ᦪ100-84+1=17,•••ᐳᨵ17e;250(3)¡Cᑭy2Ö×ijr=(240-100-a)x+80(200-x)=(60-a)x+16000(—0,஺ÜxḄ²ᜧÞ²ᜧ,ᡠÑÛß100àᨵuᓽabᵬeXYf100nabdeXYf10()nঝÛa=60,60-a=0,WM6000,(2)h¦ᑗᑭâ¦᪵ঞÛ60

21(2)'ᩚABḄ.(0ὃᦪ34sin200~0.34,cos20°~0.94,tan20°~0.36)ூ6ᫀ௃ᩚABḄ6.4.ூ9᪆௃ூ;9௃ᑖ᪆4=1
᪷?ᚁi@ᚁaABḄᐵD4i=tanaEFGH;2
᪷?JKḄᭆM'NCD,᪷?OᑗḄᭆM'NAGஹBG,GHᓽST⚪9᪆4=1
4VᚁBCḄᚁi=l46tan/BCD=—,DC3Z.ZBCD=30°+ফᙠRtABCDY,CD=BCxcos/BCD=6g3=9,2ᑣDF=DC+CF=10[V\]^GDFE_^.•.GE=DF=10[VZAEG=45°,+.AG=DE=10[ᙠRtZ\BEGY,BG=GExtan/BEG=10x0.36=3.6[ᑣAB=AG-BG=10-3.6=6.4[.64ᩚABḄ6.4.25.᝞abcABᑖdeyfஹxfgAஹBh0A=2,tanZABO=y,mᱥcy=-x2+bx+ciAஹBh.1
'bcABjklmᱥcḄ9᪆o+2
pmᱥcḄ⚔D,'4ABDḄ☢r+=3
sᚖbXfḄbcu=᝞ᙠv▲ebcABgM,eklmᱥcgN.'~t3,MNḄxIᨵ3z3{|}z,22⚓/.24⚓

221zoூ6ᫀ௃(1)y=-7x+2+(2)—(3)~t=2MNḄx1ᨵ33{4.28ூ9^51ூ;9௃(1):ᙠRtA4O8Y0A=2,ᓽ2=J_,BOBO2.♦.08=4,.A(0,2),B(4,0),c=27/ஹ8Ḅᙶ᪗ᐭ-d+bx+c4\94b=+,-16+4b+c=021,7*,•mᱥcḄ9᪆o-+—x+2,c=2pbc43Ḅ9᪆o+e,/ஹ8Ḅᙶ᪗ᐭ4\AJ4A+c=094k=--,e=2,2ᡠbcḄ9᪆o{-yx+2+(2)i஺sDE_Lyfg£,7781ᵫ(1)mᱥc9᪆o-9+—1+2=-(x--)12+,241678]78149ᓽDḄᙶ᪗(),ᑣED=-,EO=AE=E0-OA=,4164161617811749163S&ABD^SDE08_S&DEA~S&AOB=3x(--^4)X---X—X——--X4*2=---+2416241628(3)ᵫ⚪SMஹNᙶ᪗ᙳᙠbcy=-—x+2±,.M(f,-—Z+2),22,23⚓/.24⚓

2377:Nᙠmᱥc-f+]x+2.M(z,-z2+-/+2),:sᚖbxfḄbcx=f,ᙠv▲ebcgeklmᱥcgM7t:.MN=-t2+-t+2-(--+2)=-+4--(-2)2+4,ᐸY0