圆（北京版）（解析版）

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11*⚪ᑖ᪆+ᐜ᪷G@`g`hḄឋjP@`g`h6┦`ḄE᪷GᡧhḄ☢×ôÕᓽN.,¶ABCkEZC=90°,ZA+ZB=90°,...6ᙊḄØ2cm,90x^-x2:ᦑ⌱C.ὃS.ᡧh☢Ḅ.18.ூÙÚ¹௃஺0Ḅ6,SAᙠ஺0ᑁ£EᑣmoA.0A<6B.OA>6C.OA<3D.0A>3ூ&ᫀ௃A.ூ(᪆௃*⚪ᑖ᪆+SᙠᙊWEᑣd=rSᙠᙊ᜜ESᙠᙊᑁEd?EÛᓽᙊḄo.ᡠR0A<6,ᦑ⌱A.S+SHᙊḄÜ.19.ூÙÚ¹௃᝞7EABஹCD஺஺Ḅ6ᩩlEÞADஹBC./BCD=70஺Eᑣ/BADḄ©ᦪmoA.40°B.50°C.60°D.70°Bூ&ᫀ௃C.ூ(᪆௃ᡂ⚪ᑖ᪆+ᵫᙠªᙊᡈᙊkEª}ᡈ}ᡠIḄᙊᕜ`"EᓽNONBCDḄ©ᦪ.ZBADHZBCDà1ÐḄᙊᕜ`E/.ZBCD=ZBAD=60°.ᦑ⌱C.ὃSᙊᕜ`dᳮ.20.ூÙÚ¹௃᝞7EPA.á8஺஺ḄᑗxEAஹ8ᑖᑗSEá஺#ᙊvSC,/4P8=60஺EPC=6,ᑣACḄ^mo

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14•Ḅᦪ5஺°Vjᵨᙊ5i᝞>\]O,/.ZB-65*"CA=CD,.*.ZBDC=Z3=65°/.ZACD=50°,Ḅᦪ50°ὃ2ᡧ5ஹஹḄᐵᚖ6ᳮ.22.ூ¢£;௃᝞>2AஹBஹPC஺O¤Ḅj2¥/APB=45°,ᑣNAOBḄᦪ
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18tTᫀ௃B.ூV᪆௃X⚪ᑖ᪆\]0C,ᵫᚖ6ᳮf®2ÊCDḄA2,ᵫA3=12,Ë3P:.Ì=1:fi3?ḄÍÎe0?ÍfiᙠRtZkO?CA᪷ÅÏÐ6ᳮᓽfa¼ÊC,ᓽfa¼CD.\]0C᝞>\•CDJ_A3,AB-12.3P/=1:5.'.BP=2/.0P=6-2=4ᙠRtAOECACP=yl0Cz-0Pz=275CD=2CP=4#ᦑ⌱B.ὃ21.ᚖ6ᳮ2.ÏÐ6ᳮ.28.ூÓÔ;௃³®ᙊ┵ḄÖ☢F3cm,×ØÍ5cm,ᑣÙᙊ┵ḄÚ☢R()7)),A.15Û஺"B.20᳘ÝC.25/rc"D.30&"ூTᫀ௃A.ூV᪆௃X⚪ᑖ᪆ᙊ┵ḄÚ☢R=Ö☢ᕜÍX×ØÍ+2,ßHàᦪáâᐭᓽfiV.ᙊ┵ḄÚ☢R=2"><3X5+2=15=.ᦑ⌱A.ὃ2ᙊ┵Ḅäå.

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