2019-2020学年广西桂林市秀峰区八年级（下）期末数学试卷（附答案详解）

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2019-2020
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ᓽB34:23.ூCᫀ௃(1)34FG஺I஺MJ.48,,:BDJ4BCḄKᩩᑖN0E=0M,,:0E=OF,OF=OM,.•.4஺NBACḄᑖNᓽG஺ᙠ484cḄᑖNP:(2)•••G஺ᙠN8ACḄᑖNP1•-0E=OF=OM.•••ᙠRt78BC-AC=5,BC=12,AB=V52+122=13,1.——S4ABe=5x12x5=30.1111•••SMBC=S&OBC+SAAOC+S.AOB=2X120E+-X5OE+-x13OE=-X300E=15OE=30,OE=-2.ூ᪆௃(1)FG஺I஺M1AB,ᵫᑖNḄឋROE=OM,ᵫSTḄឋR஺E=OF,᧕R஺M=OF,ᵫᑖNḄᑨᳮRG஺ᙠNB4CḄᑖNP:(2)WXOC,᪷>Ḅ☢Z[\ᓽBR];<.⚪^⌕ὃḄᑖNḄឋ`ḄᑖNPḄGᑮḄbḄcd@Ce⚪Ḅᐵ".24.ூCᫀ௃(1)ᵫ⚪fghijgᜩḄlmnxᐗp✂]rḄijsyh,᪷>⚪fRy=200-4x-,z102y=--%+200.(2)ughijgᜩḄlmnxᐗ᪷>⚪fR(180+%)(-|%+200)=38400.᦮ᳮwR/-320x+6000=0.R=20,x=300.2z{=20}x+180=200(ᐗ).16⚓ᐳ20⚓

16z{=300}x+180=480(%).CᜩḄghijḄl200ᐗᡈ480ᐗ.ூ᪆௃(1)ughijgᜩḄlmnxᐗp✂]rḄijs)h᪷>p✂ᨵij200hizghijḄlsgᜩ180ᐗ}ijាᐰ:᝞ghijgᜩḄlgmn10ᐗ4hij]rBᑡ]ᦪ\.(2)38400ᑭ¡᪷>ljḄᐵ¢BᑡT£¤].⚪ὃᳮ⚪fḄ¥8ᐵ"⍝§ljḄᐵ¢⊤©]ᐵ¢᪷>ᑭ¡Isªᐵ¢BᑡT£¤.25.ூCᫀ௃(1)20,(|,20):3(2)uNA8Ḅ᪆\syi=/qx+²³G4(0,30),B(0.5,20)µᐭRy1=-20%+30,♦:AB"CD,•uNCDḄ᪆\sy=-20%+b,22³GC(l,20)µᐭR&=40,2ᦑs=-20%+40,uN£Ḅ᪆\sy=+¼3³GE(,30),H(|,20)µᐭRk=K60,À=Á஺3.•.y=-60x110,T£ÂÃÄÅ*°È:Ê3+:•/ஹ஺ᙶ᪗s(1.75,5),30-5=25(/cm),ᡠÐÑÒ]Ó1.75Ñ}wÔᝤᝤÖPe}c×25kmK(3)³y=0µᐭNCQ᪆\ᨵ-20x+40=0,RÙ=2,³y=0µᐭNEḄ᪆\ᨵ-60x+110=0,RÙ=Ú,2--=i(/i)=10(ᑖÛ)66ᦑÑÒÜ⚜Þ}hß10ᑖÛᑮàJᙢ.

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