海南省定安县2021-2022学年中考数学模拟试卷（三模）含解析版

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10ᳮḄ«ÎBCḄ»᪷6Ὺ·µ[µ½ḄឋÐÊËÌᳮªBO,0D',ÑÒªº½ABODḄᕜ».ூ0.௃.4᝞xÓÔ8C,8ᙠ)µ¸/஺&YB'C'=AB'=3,ᙠRtZ\N5'஺'"C'=y/AB'2+B'C'2=3V2:.BC'=36-3,ᙠῪOB=BC'=36-3,ᙠ·µ[µ½08c0C=6(372-3)=6-3721B.0஺=3-஺Ö7=3×-3,º½Ḅᕜ»942AD'+OB+OD'=6+372-3+3Ø-3=672.ᦑ⌱4A.ூfÙ௃Ú⚪ὃÛÜÂÃḄឋÐஹ¼"½ḄឋÐ%ØῪ·µ[µ½ḄឋÐ.Ý⚪Þ@〉ᶇ7ÓÔ3஺᪀⌼ῪRtaOBC9.⚪Ḅᐵäᶇ7ÂÃḄ)åᐵæ.13.᝞xᙠç½4BCQ48=4,4D=5,AD,AB,BCᑖÅ0஺ᑗaE,F,G[f,èf஺é0஺Ḅᑗ¸Æ8Caf"ᑗfN,ᑣ஺MḄ»()C4D.23N11⚓/R23⚓

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13ூ0-௃`⚪-᪆Abᑖc6A2+3x=x-2,-6Ax=—2.defX=-2
ᑖNZ_Ḅ-?ᑣᑖNZ_Ḅ-@Ax=-2.ᦑ*ᫀ@x=—2.17.᝞4?iῪklaABC&?AB=AC=8,mAB@knḄoᙊ0qrsBCtD,ᑣᨩvwᑖ☢y@z{|}ᶇᐔ.ூ*ᫀ௃24-4ᐔ.ூ-᪆௃ூ0-௃-AAD,0D,;iῪklABC&,/.ZABD=45°.VAB
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iῪkll,AD-BD-VAB=8,AD=BD=4-y2?•,S*^=S3ABC-SAABD-SAD=SAABC-SABD-(SsogAOD-yS&ABD)A14⚓/23⚓

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.ூ*ᫀ௃-2ூ-᪆௃ூ0-௃`⚪-᪆ABE=x,ᑣEF=x,CE=8-x,ᵫᢚ]6?AF=AB=6,ᵫ£¤¥ᳮ?]6§7m'=10,A.Cª=10-6=4,ᙠRt^CER&?ᵫ£¤¥ᳮ]6,—+42=(8—x)2,-6x=3,:BE=3,CE=5,ᵫᢚ]6,NAEF=-ZBEF,ZGEF=-NCEF,22NAEG=[ZBEC=90°,ZCEG+NAEB=90஺,2°NBAE+NAEB=90",ZBAE=NCEG,°ZB=NECG=90°,:AABES^ECG,15⚓/23⚓

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166ᐵ8x,yḄ=ᐗ?@ABᓽ./6CD.⚪᪆!AᧇᐭᑺX8ᧇᐭᑺN,30x+70j=270᪷&⚪F/:Kx=l,x=2/,=3.4ᧇᐭᑺ28ᧇᐭᑺ3.21.N,OPQRSTḄUQVWSTXY,Z[\ᐙᵯ_Y`Ḅa@ᦪᑖNA,B,C,DefghᐸjklghḄa@mnN200ᓟp210ᓟp220ᓟp230ᓟpq/᝞stuvḄwxy.z᪷&yj{|Ḅ}~sᑡᡂ:ᐙᵯᩩᐙᵯᡧᦪ(1)WnZ[ḄPQRSTᐳᨵ..;(2)\y1⊡ᐙuvᙠy2jCghᡠᓰḄᙊ..;(3)xWPQRSTᐙᵯ_Y`Ḅᙳa@ᦪNᓟp(ᑮᓟp)ூᫀ௃(1)100(2)72(3)xWPQRSTᐙᵯ_Y`Ḅᙳa@ᦪN214ᓟp.ூ᪆௃ூ௃⚪ᑖ᪆(1)ᑭᵨ஺ghḄᦪᡠᓰḄᑖ'.x6Z[ḄᵯSTḄ4ᦪ;(2)ᵨ஺ghᡠᓰḄᑖ'360஺./CghVlḄᡧ¢Ḅᙊ;(3)᪷&⚪Fᑡ£xᓽ..⚪᪆(1)12-12%=100,WnZ[ḄPQRSTᐳᨵ100;ᦑᫀN100100-8-60-12(2)᝞yᡠ§CghᡠᓰḄᙊ360°x---------------=72.100ᦑᫀN72(3)200x8+210x60+220x20+230x12017⚓/423⚓

17=1600+12600+4400+2760=2136021360-100=213.6-214©ᓟpªxWPQRSTᐙᵯ_Y`Ḅᙳa@ᦪN214ᓟp.22.4ஹ8«k¬150ᓟpᑖ®4ஹ8ᜐ°/±²³CᜐḄ?´᝞yᡠ§±²³³µCNᙊ45ᓟpN¶·Ḅᙊtana=1.627,tan^=1.373.N,¸¹º»ᨵᐵ¼½!x¾¿ÀÁ«ḄÂÃÄÅ.ÆÀÁÂÃÄÅQᔲÈɱ²³z▊Ëᳮᵫ.ூᫀ௃Z8tÈɱ²³.ᳮᵫÎ᪆.ூ᪆௃ூᑖ᪆௃ᑖ᪆✌ᐜÉ஺ÑÒ஺ᵫ⚪F/AACD=a,NBCD=B&ᓽ./ᙠÓ"48jAD=CD-tana,ᙠ7?88jBD=CD,tan஺,ÔÕ./CDtana+CZ>tanW=N3,ᑣ.×/CDḄØᓽ.ÙÀÁ45ÂÃÄÅQᔲÈɱ²³.ூ௃48tÈɱ²³.ᳮᵫ᝞sᑣᙠRtAACDjAD=CD-tana,ᙠ/?/Zk8CDjBD=CD&tan0,*.*AD+DB=AB,CDtana+CD”an6=/B.“4B150150•CD-_____=__________=___#tana+tanp1.627+1.3733VCD=50>45,018⚓/423⚓

18.♦•ÂÃÄÅtÈɱ²³.ூÛÜ௃Ý⚪ὃß,?ᔣᡂáâ8?ᔣ᪀⌼åæ¢çᑭᵨåæ¢ḄÙè×⚪Ḅᐵé.23.᝞yêfëØkgḄgëAABC4ACDìᡂí¢ABCD,ÛEஹFᑖðñCBஹDCòḄÛ(EஹFÒBஹCஹDtóᔠ)õKåöᢝBE=CF,ÀCAEஹAFஹEF.(1)×ø©AABE^AACFঝ4AEFgëæ¢(2)জýÛEþᑮÿᙢEF±DC?ঝAB=4,NEAB=15஺ACEFḄ☢.ூᫀ௃(1)জ#$%&᪆(ঝ#$%&᪆((2)জE*+ᑮBE=BCEF±DC(ঝ4CEFḄ☢-2G.ூ&᪆௃ூ/&௃0⚪ᑖ᪆3পজᵫ6789:Ḅឋ<ᓽ>?@ᓽ>?@AB(ঝᵫᐰ689:Ḅឋ<ᓽ>?@AB((2)জᵫD989:Ḅឋ<@NFEC=30°INAEB=3G஺,ᓽ>?@AB(ঝᐜ@ZAEB=45஺,KᵨMNOᳮ@CF=EB=2Ji-2,KᑨU@^ABG^FCH,ᓽ>@EC=2ji+2ᵨ89:Ḅ☢XYᓽ>?@AB.0⚪&᪆3(1)জ#$3IZZCDᙳ-6789:AB=AC,ZABC=ZACD=60°,.ZABE=ZACF=l20o.BE=CF,:."BE/"CF.ঝ#$3•:“BE/"CFAE=AF,NEAB=ZFAC,.ZEAF=ZBAC=60°.]19⚓/a23⚓

19:.“EFb6789:.(2)জERLDC,-.■ZECF=60°,./EEC=30஺,\-ZAEF=60°,AAEB=30°,NAEB=NBAE=30°,BE-BA..E*+ᑮBE=8CEFLDC.ঝ᝞defgh4GL5CifG,efjhj_LECif”;NEAB=15஺,ZABC=60°,.ZAEB=45஺,ᙠRtz^GBl,ZABC=60°,Z8=4.BG=2,AG=2y/3.:.AG=GE=22:.CF=EB=243-2.,.FABGSAFCH,AGFH~AB~~FC':.FH=3-ᓱ.EC=BE+BC=2y/3+2..•."CEEḄ☢-31X(2V3+2)(3-V3)=2A/3.24.᝞d1,mnoᦪqax2+bx+cḄdrsxtᑖuviAஹBxfsytvifC.]20⚓/a23⚓

20tanZABC=3»}ᐗmnax2+bx+c=0Ḅx᪷--8ஹ2.(I)mnoᦪḄ&᪆Y((2)D1fAAB-ᙢ┐ᑮACᙢl1sBCvifD,PbADḄlf.জfPḄ*+(ঝ᝞d2,efDhDEᚖDxtifE,hDF_LACᡠᙠDifF,APEஹPF,ᙠI*+elNEPFḄᜧᔲᦋ▊$ᳮᵫ(ூ&᪆௃ூᑖ᪆௃(1)ᵫy=ax2+bx+csxtᑖuviAஹBxf£}ᐗmn஻/++°=0Ḅx᪷-}8ஹ2,>?fAஹfBḄᙶ᪗ᓽ>?ᑮ0BḄ§¨ᵫtan/ABC=3,?ᑮfC(0,-6),ªAஹBஹCḄᙶ᪗«ᐭmnoᦪlᓽ>?ᑮmnoᦪ&᪆Y((2)জ᝞d6.1,1ᙠABᙢPᓽ-ABḄlfH,1*+ᑮACᙢPᓽ-ACḄlfK,ᦑPḄ*+-4ABCḄlHK,ᙠRtABOClᵫMNOᳮ?ᑮBCḄ§Kᵫ89:lOᳮ>?ᑮHKḄ§ᓽPḄ*+(ঝ/EPFḄᜧ²³ᦋ.ᵫiP-RtZXAEDµ7ADḄlfᦑPE=/AD=PA,¶·ZPAE=ZPEA=—ZEPD,¹ᳮᨵNPAF=NPFA»ZDPF,ᓽ>?¼ljNEPF=2/EAF,ᦑ/EPF22Ḅᜧ²³ᦋ((3)¾4PEFḄᕜ§-C,ᑣC“EF=PE+PF+EF=AD+EF,ᙠ6Ὺ89:PEFlePhPG1EF]21⚓/a23⚓

211OC3EG3ifG,?ᑮNEPG=—NEPF=NBAC,ᵫitan/BAC=——=}ᦑtanNEPG=——=-,2AO4PG436338?ᑮEG=-PE,EF=-PE=-AD,AMfnWC=AD+EF=(1+-)AD=-AD,¨AD±BC,bPEFADᨬÃQpᓽᨬᵫS8c=30,?¼UAD=3jid¶·?ᑮC.ᓽᨬÄ.ூ/&௃&3(1),oᦪÅ=஺/++஺ḄdrsxtᑖuviAஹBxf£}ᐗmnQ/+/?x+c=0Ḅx᪷-}8ஹ2,AA(-8,0)ஹB(2,0),ᓽOB=2,¨,.tan/ABC=3,/.OC=6,ᓽC(0,-6),ªA(}8,0)ஹB(2,0)«ᐭÆ="2+È}6l64஺-86-6=04஺+2Z?-6=03a=

22VDEIAB,ᙠRtAAEDlP-µ7ADḄlf/.PE=—AD=PA,2AZPAE=ZPEA=—ZEPD,¹ᳮ>?3ZPAF=ZPFA=—ZDPF,/.ZEPF=ZEPD+ZFPD=222(ZPAE+ZPAF),ᓽNEPF=2NEAF,¨3NEAFᜧ²,NEPFḄᜧ²³ᦋ((3)¾4PEFḄᕜ§-C,ᑣC;PEF=PE+PF+EF,#PE=.AD,PF=yAD,C=AD+EF,PEFᙠ6Ὺ89:PEFlePhPG_LEFifG,/.ZEPG=-ZEPF=ZBAC,2.,OC3,EG3,363.tanZBAC=-----=—,tanZEPG=------=—&EG=-PE,EF=—PE=-AD,AO4PG455538•4Ë=AD+EF=(1+1)AD=1AD,¨AD_LBC,ADᨬÃ஺ᓽᨬ/#5^^=30,]824_AyBCAD=30,/AD=3·(•ᨬÄ-3|AD=yV10.ூfÍ௃Ã⚪n⌕ὃÐÑmnoᦪÒᔠÔÕOÖᦪÈmnoᦪ&᪆YID989:lḄឋ<6×ØᵨAD⊤Ú@4PEFḄᕜ§b&⚪ᐵÜ.]23⚓/a23⚓