江苏省宿迁市泗阳2021-2022学年中考数学猜题卷含解析及点睛

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=90m(2)90-25-10-5=50,

16Ò<ÓÔÕÖᵨᐳ×ᓫÙḄÌÚ⊡ᐰᩩlÝÞg(3)3000xᡈ=750(ß)200H=ᜩḄáÅâᙠ24ᓟäḄᜧå750ß69(22ஹ20ஹ(1)yߟߟ;(2)(---->0)ᡈ|¯--,0x3k3ூ᪆௃(D®A%ᙶ᪗°ᐭU᪆C"ḄᑣCA%ᙶ᪗d®A%ᙶ᪗°ᐭéê᪆CAḄ,Céê᪆(2)ëP(x,0),ᑣ⊤iPCḄìÀ¯í⊤iAACPḄ☢¼ᑮᐵxḄCî%Ḅᙶ᪗.ூ௃H(1)®A(2,஻)°ᐭU᪆H஻=3,...A(2,3),®Aᙶ᪗°ᐭîð=6,xᑣéê᪆Iñ9.X(2)Uî;x+2,óy=0,ᑮx=-4,ᓽC(-4,0).ëP(x,0),PC=|x+4|.•..ACñ☢¼I5,4|x+4ô3=5,ᓽ+4|=2,222Hñ-öᡈ--433

17ᑣPᙶ᪗(go)ᡈ(-஺).21ஹ(1)(4,0)m(2)-l.22ஹ(1)\G᪆m(2)272+1.ூG᪆௃ᑖ᪆`(1)ஹ᪷ᚖḄÈÉÊv!vËᫀm(2)ஹ᪷ᚖ?ÍḄឋ>!vDFஹDE?EFḄÑÒÓ!vËᫀ.¦G`(1)᝞EFᡠÊm

18BC(2)H,÷lABCD-øl.,.ZBDC=15O,CD=BC=LùTEFᚖUSᑖCD,AZDEF=90°,ZEDF=ZEFD=15°,DE=EF=CD=2,DF=&DE=2ú,/.DEFḄᕜì=DF+DE+EF=2a+1.%&H'⚪û⌕ὃ*Ḅ-ᚖḄឋ}~Ạ⚪ý.ᳮᚖḄឋ-⚪Ḅᐵ/.23ஹ(1)j=-8x+2560(300,-30>0,100->0,ᓽ-8xḄ9:6(2);<ᡠḄ4ᦪ<>?4ᦪ,XXᵫABឋ-DyExAᜧGBHᑣJx=lKyᨬM)N8ᨬM:ᑏ8PQᫀ.⚪S᪆(DᵬxᔴAᑣᵬBḄᨵ(1-x)ᔴAḄᨵᔴBḄᨵ50-(1-x)=(x-30)ᔴᡠTy=14x+20+10(1-x)+8(x-30)=-8x+2560,xḄ9:WX30WxSL(2)ᵫ(1)y=-8x+2560yExAᜧGBHᡠTJx=lK"#ᨬMJx=lKy=-8x1+2560=1920,YKQᫀ<ZᵬḄᐰA20ᔴAḄḄᐰB.ὃ\>?4ᦪḄ]ᵨ.324ஹপ`S᪆;ফc.2ூ᪆௃(1)deO஺ᵫZ)"_LAC,஺”X஺஺ḄᑗiᯠkᵫlmiḄᑨo1ឋp-qNC=NO08,ᵫᙊᕜtoᳮ-NOBD=NDEC,vGNC=NOEC,-qwxᡂz6(2)q{|஺}᪷~tḄឋpᓽ-N8ᙊḄ.

19ூS௃(1)q{deOD,ᵫ⚪DHJ_AC,ᵫDHX஺஺ḄᑗiZODH=ZDHA=90°,/.ZODH=ZDHA=90°,.,.OD/7CA,/.ZC=ZODB,,.,OD=OB,.".ZOBD=ZODB,.*.ZOBD=ZC,,/NOBD=NDEC,.•,ZC=ZDEC,.•.DC=DE(2)Sᵫ(1)-DOD஻AC,:.ZODF=ZAEF,■:NOFD=NAFE,/.OFD^AAFE,.EF_2_AE••GGVAE=1,.".OD=—,2.•.OOḄ