陕西省西安市2021-2022学年八年级下学期期末考试数学试题（解析版）

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2021-2022
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17-%>60.ᦑ⌱C.ூMN௃O⚪ὃQ!"ḄS▭UᵨWX⚪Y=UḄᦪ[ᐵ]^7⚪Ḅᐵ_.9.᝞aᙠcdA8CDeEᙠAOfghi48£jkᢚmJM4ាopᙠcdABCDḄqer஺ᜐAB=4,ᑣḄu^GvB.473C.8D.12ூᫀ௃Bூ7᪆௃ூᑖ᪆௃wx0஺✌ᐜ{|0ஹ஺ᐳᵫᢚmḄឋC=OB=AB=4,==vᑭᵨᳮᓽ=8cḄu.♦.,M஺^cdA8C஺Ḅqer.Bஹ஺ஹ஺ᐳ,NC=90஺,•••AABEBEᢚAាopᙠcdABCDḄqerOᜐAB=4,BD=2OB=2AB=2CD=8,BC=y/Blf-CD2=V82-42=46•ᦑ⌱B.ூMN௃O⚪ὃQadḄᢚm⚪erqcdḄឋᳮ!A.7⚪Ḅᐵ_ᑭᵨᢚmḄឋ

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9ூg᪆௃ூᑖ᪆௃᪷k\"ḄឋmnACB஺CD//AB,AO=-AC=Scm,BO=-BD=6cm,tuᑮ22AB=y]AO2+BO2=10cm'ᯠ0}ABOḄ~஻᪷k\"Ḅ☢gACxBD=A3x/in48h,,ᓽnMg.ூg௃gᙠ\"4BCO7ACLBD,CD//AB,BD=12cm,AC=16cm,AO=AC=8cm,BO=BD=6cm,•AB=4AOT+BO1=10cm}ABOḄ~஻\"ABCDḄ☢-ACxBD=ABxh,2148ᓽ.x16x12=10x/?,gh=—,25EFLAB048..EF=h=—cm.548ᦑᫀyூ௃⚪⌕ὃ\"Ḅឋmᳮ+,\"Ḅឋmᳮ*g⚪Ḅᐵ).16.᝞!AB//CD,AD//BC,4)=5,BE=8,AOCEḄ☢6,ᑣO"A8C£Ḅ☢.ூᫀ௃20ூg᪆௃ூᑖ᪆௃3GL8EG,“᪷kA3CEḄ☢6,MYOG,᪷kN&¥_¦ḄPQ5ᑮA”Ḅe᪷k&¥O"Ḅ☢¨©ᑮᫀ.

10ூg௃g᝞!஺GL8EG,”,:AH=DG,■:ABHCD,O"ABCD*&¥O".BC=AD=5,$•BE=8,:,CE=3,ª,••«QCEḄ☢6,.-DGCE=6,2.DG=4,.O"ABCDḄ☢=BCxAH=20,ᦑᫀ20ூ௃⚪ὃḄ*&¥_¦ḄPQ+,N&¥_¦ḄPQ5&¥O"Ḅឋm¬☢¨©*g⚪Ḅᐵ).17.᝞!ᙠ®"A8CD7AB=4,AT>=2EOCOḄ7Pᙠ_¯A6°±²*CPḄ7ᑣACEFḄᕜeḄᨬEµ*.ூᫀ௃20+2ூg᪆௃ூᑖ᪆௃ᵫ⚪·᪷k¸¹"Ḅ7º_ḄឋmᑮEF=^PD,»IJCACEF=CE+CF+EF=CE+?(CP+PD)=/(CD+PC+PD)-1CDP,¼4CDPḄᕜeᨬE½Z\CEFḄᕜeᨬEᓽPC+PDḄµᨬE½ACEFAC

11ḄᕜeᨬE¾DᐵABḄ¿D',ÀÁCD'bABP,Âuᑖ᪆ᓽnᑮ9Ã.ூg௃gCD7FCP7.\EF=yPD,•••CACEF=CE+CF+EF=CE+T
CP+PD=ÄCD+PC+PD=^CCDPA.•.¼4CDPḄᕜeᨬE½4CEFḄᕜeᨬEᓽPC+PDḄµᨬE½4CEFḄᕜeᨬE᝞!DᐵABḄ¿T,ÀÁCT,ᑣPD=PT,•.,AD=AT=BC=2,CD=4,ZCDT=90°,CT=7CD2+DT2=V42+42=4>/2-ACDPḄᕜe=CD+DP+PC=CD+PT+PC,VPT+PC^CT,.•.PT+PC24.•.PT+PCḄᨬEµ40,/.«PDCḄᨬEµ4+4*'•CACEF=yCACDP=2V2+2-ᦑᫀ2&+2.ூ௃⚪ὃÅ¿-ᨬÆPQÇ⚪¬¸¹"ḄᕜeḄÈÉVWg⚪Ḅᐵ)*UÊᑭᵨÅ¿gËᨬµÇ⚪.ஹ⚪ᐳ8⚪69ᑖ.ᑏ18.ᓄÌ,..ci~—3cici—3প———ᓝÏ1Q+஺a—1

12m-2(2)\m+2—--m-2J2m-6ூᫀ௃(1)ci~\m+3(2)----2ூg᪆௃ூᑖ᪆௃(1)ᑖ©ḄᑖÑஹᑖÓÔÕ©ᑖgḄᐜÕ©ᑖg6½ᑭᵨ◀ØØᑣ#"ᯠ0Ùᑖᓽn;(2)ᐜÛÜÝᑁḄ©ÑÂ¥ßᑖᑭᵨ6ᑖÓḄᑖ©àØØᑣÂ¥ÈÉáÉᑖ©ḄâØᓽn.ூEÇ1g௃Q(Q_3)(6Z+l)(6f-l)g:ä©==a-\-a(a+l)a—3ூEÇ2g௃ë2_"5m-2_(m+3)(/7i-3)m-2_m+3g:ä©=m-22m-6m-22(m—3)2ூ௃⚪ὃᑖ©ḄᓄÌ+,ᑖ©Ḅ±ÉØᑣ*g⚪Ḅᐵ).2+x319.gïð3——-x—2.2—xூᫀ௃x=2ூg᪆௃ூᑖ᪆௃ïðNO4â(x-2),-ᑖ©ïðᓄ.ᐗ.òïðg.ᐗ.òïðᓽn.ூg௃ïðNO4â(x-2)3(x—2)—(2+%)=-3,᦮ᳮ2x=5,gX——,2õö¼x=?½x—2=2—2='÷0,222ᦑäïðḄgø=2.2ூ௃⚪ὃgᑖ©ïðᐸúûü*-ᑖ©ïðᓄ᦮©ïðý·ᨬ0⌕õö.20.᝞!ᙠAABC7AB=AC,N84C=36°,
ᵨᙠ4cP,BP,8AABCᑖᒘᡂῪ!".(%ᑏ'(ᶇ*+)

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