2022-2023学年广东省八年级（上）开学数学试卷（含解析）

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2022-2023
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8ZD=45°,ᑭᵨ!HI᜜HḄឋÁ(*ÇÈ.C⚪É⌕ὃE¢!HIḄᑁH¡Jᳮ¾¦¿ḄឋÁJᳮ¡᜜HḄឋÁ{;4஺ḄᦪOKC⚪ḄᐵN.10.ூLᫀ௃AK%জ•••48஺¡4CDEO5ᐰGḄG!HI•••CA=CB=CD=CE,Z.ACB=60°,4DCE=60°,Z.ACE=60°,4ACD=4BCE=120°,ᙠ4஺஺¡4BCE6(CA=CB(Z.ACD=BCE,{CD=CE•••,ACD^^BCE(SAS),ᦑজlQঝ•••,ACD=^BCE,•Z.CDA=CEB,MFN=Z.EDF+FED=Z.EDF+FEN+NED="DE+NED=120°,ᦑঝlQঞ•••,ACD=^BCE,•Z,CDA=CEB,vCA=CD,:.Z.CDA=CAD,:.CEB=/-CAD,ᙠÊECM6ZCAN=Z.CEMAC=EC,zACN=ECMACN"ECM(ASA),ᦑঞlQট•••,ACN=^ECM,CN=CM,vMCN=60°,••CMNkG!HIᦑটlQÇÍlQḄᨵজঝঞটᐳ45ᦑ⌱%A.

9........জ᪷'G!HIḄឋÁ*C4=CB=CD=CE,4ACB=60°,DCE=60°,ᑣOONACE=60°,ᑭᵨ“SAS”(ᑨ?4CD!BCE....ঝᵫACD=^BCE*ᑮNC/M=“BE,ᯠ/᪷'!HI᜜HJÒ()ᑨ?ঝlQ....ঞᵫÊBCE*ÓIJ/CZM=/.CEB,ᯠ/᪷'"ASA"ᑨ?ACNNABCM..ট᪷'ᨵZ5HO60ḄGῪ!HIOG!HIᓽ(Ö¦ᑨ?.郝郑..C⚪ὃE¢ᐰG!HIḄᑨJ¡ឋÁG!HIḄឋÁ¾¦¿ḄᑨJH¾ᑖ¿Ḅ..........JÒ×ØÙÚᐰG!HIḄឋÁOK⚪ḄᐵN.................OO11.ூLᫀ௃77-3....K%J(3-ᐔ)2=d(jt-3)2=7T—3-.鼠...ᦑLᫀO%7T-3...蒯p᪷ḄឋÁ%=a(a>0),᪷'p᪷ḄឋÁ()3Þᓄß.笈I-C⚪ὃEḄOp᪷ḄឋÁ¡ᓄà᪷'p᪷ḄឋÁ3bᦪÖ¦ᓄà....-.£......郑....12.ூLᫀ௃7.....氐K%q¶=3,y=2bᐭRi6x+by=32,*OO.6x3+2b=32,.热...â⚗72b=32-18,..祖...ᔠãäå⚗®ᦪᓄk1,*b=7.期摒邮æx=3,ç=2bᐭRi6ᑐ+Ê=32,quᦪéᓄkêuᦪᯠ/Kᐵëu®ᦪ......bḄRi...氐........C⚪ḄᐵNOæRiḄKbᐭìRiqᐵëíஹyḄRiéᓄkᐵë®ᦪbḄRi0.....姆.....冰..{;bᓽ(.OO....13.ூLᫀ௃130°....ூK᪆௃..ூᑖ᪆௃氐S.C⚪ὃE¢3⚔HG⊡HḄJÒOïẠ⚪×ñᭆóឋÁãôQ¯õOK⚪.......ḄᐵN........᪷'3⚔HG(*41=42,0{;41,ᯠ/᪷'⊡HḄJÒᑡö÷ᓽ(*K.....OூKL௃O...K%ᵫ3⚔HG(*41=42,....Â10⚓ᐳ18⚓...

10VZ.1+Z2=100°,•••Z1=50°,ABOC=180°-Z1=180°-50°=130°.ᦑLᫀk:130°.14.ூLᫀ௃50஺ᡈ130஺K%᝞õ1ᡠw%"AM,DNᑖ:;BCஹEFÞḄý,4cM¡4DFNᙳkÿ
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.♦.•ᙠRtACM^RtDFN(AC=DF14M=DN'@.RtAACMARt,DFN(HL).•••4DFN=4ACB=50°.•••DFE=130°.ᦑ.ᫀ50஺ᡈ130஺.ᑖ2345
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