2020-2021学年广西南宁九年级（上）联考数学试卷（附答案详解）

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2020-2021
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13MDNE2ᵫ⚪AC—80mm,CD—80mm,Z-DCB=80°,Z-CDE—60°,ᙠRtCDNCN=CD-sin^CDE=80xy=40V3mm=FM,zDC/V=90°-60°=30°,••!DCB=80°,•BCN=80°—30°=50°,•••AMIDE,CNIDE,:AM“CN,LK=(BCN=50°,4CF=90°—50°=40°,ᙠRt4FCAF=AC-sin40°=80x0.643«51.44(mm),AM=AF+FM=51.44+4073«120.7(mm)AᑮOEḄ120.7nun(2)CD!᝞3ᡠ$᪷&⚪4DC8=80°+10°=90°,ᙠCD=80mm,BC=40mm,•tanzZ)=—=—=0.500,CD80•!Dx26.6°,'(Ḅ)*60°-26.6°=33.4°,CZ)Ḅ)*33.4஺.ூ.᪆௃(1)234ᚖ᪀⌼)7)8ᑭᵨ)7)8Ḅ;)ᐵ=>?CNஹAF,ᓽ>?AᑮZ)EḄ(2)A?!Ḅ8Bᔠ8DE8ḄFḄ;)Gᑭᵨ)7)8Ḅ;)ᐵ=>?HIḄ)*ᓽ.J⚪ὃL)7)8Ḅ;)ᐵ=┦)7)NᦪḄP234QR᪀⌼)7)8S14⚓ᐳ18⚓

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