福建省福州2021-2022学年七年级上学期期末数学试题（解析版）

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2021-2022
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6ூᑖ᪆௃᪷qªñḄᑨççᳮᓽ^.ூ௃ᵫ⚪1QjuNABC=NDCB,.•.AB஻CDUᑁ┯MÉ5$áñqªVᦑÛᑁ┯MÉ5$áñqª.ூ;<௃⚪ö⌕ὃ?qªñḄᑨç5⚪ḄᐵAB÷qªñḄᑨççᳮ.213.N2x4"B&⚗5ᑣ01=,n=.ூᫀ௃জ.1ঝ.6ூ᪆௃m+1=2m=1ூ௃ᵫ⚪1\c,,஻2=472=6ᦑᫀR1,6.14.᝞j5øùìMíḄáM⚔;¸ᔠ,᤮¹ᙠü☢Å5ÂNBOC=ýNAOD,ᑣNAOD=ூᫀ௃144°ூ᪆௃ᑖ᪆௃᪷NA0D+NB0O180஺᪷NBOC='NAODNAOD,ᓽᫀ.4ூ௃VZAOB=ZCOD=90°,AZAOD+ZBOC=ZAOB+ZDOB+ZBOC=ZAOB+ZCOD=90°+90°=180°,1VZBOC=-ZAOD,41ZAOD+-ZAOD=180°,4

7.\ZAOD=144O.ᦑᫀ#144°.ூ%&௃'⚪ὃ*+,-.⊡-Ḅ1ᵨ3NAOD+NBOC=180஺:;⚪Ḅᐵ=.15.?@Aᦪ஻?,"EFGHI*஻=(᪷+2>-2஻.O2*஺=4*(-3),ᑣ஺=.ூᫀ௃-13ூ᪆௃ூᑖ᪆௃᪷SḄTEFᑖU2*஺V4*(-3)ḄW᪷2*஺=4*(-3)ᐵ@”ḄᐗZ[\ᓽ.ூ௃],^/«*஻=(᪷+2)2-2",2*a=(2+2b-2a=16-2a4*(-3)=(4+2b-2x(-3)=42,2*a=4*(-3),16-2a=42,a=-13,ᦑᫀ#]13.ூ%&௃'⚪ὃ*ᐗZ[\ஹTEFfAᦪḄGHgᑁiᳮ⚪klSḄTEF:⚪Ḅᐵ=.16.%A,B,Cᙠno/pAB=a,BC=b,ACߟߟ,ᑣ@=__________.2b2ூᫀ௃2ᡈ;ூ᪆௃ூᑖ᪆௃ᑖuvwC%ᙠAḄxy.C%ᙠAḄzy{|uv}~ᓽ.ூ௃]C%ᙠAḄxyᨵb-%=a2.3a:ஹb—2a_2ᔆC%ᙠAḄzy,aᨵ/7+—=a2

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x+53ᵫ⚪+—----=80804

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\]ᳮN=2ZDMN_`aOP\ᡠ[/AGE=Na\b_`/AGE=/FGBa\ᡠ[N=NFGBa\ᡠ[AB஻CDa\.ூ6ᫀ௃dTᑖeḄfgDMF,DMF,hᣚj⚔dlDMF,hᣚ]mdlnoeTp.ூ(᪆௃ூᑖ᪆௃᪷dTᑖeḄfgrᐵNAGE=N஺sF,$᪷j⚔dlrᐵNDMF=/FGB,$᪷TpeḄᑨfuᓽ.ூ,(௃_`G”Tᑖ/AGEaOP\ᡠ[N4GE=2NAGHadTᑖeḄfg\]ᳮNOMF=2/£>MN,_`v4GH=NDMNaOP\ᡠ[/AGE=/£>MFahᣚ\NAGE=/FGBaj⚔dl\ᡠ[ahᣚ\

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?E=90°,0CTᑖ/40F,ZC0F=35°.
1Ḅᦪ
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2ᵫNCOF=35஺ZCOE=90°,NEOF=55஺,$ᵫTdḄឋᑮNBOE=55஺ᓽᑮOETᑖNBOF.ூ,(௃a1/COF=35°,OCTᑖNAOF,ZAOC=35°,.ZBOD=AAOC=35°.
2OETᑖNBOF.ᳮᵫ᝞'ZCOF=35°,ZCOE=90°,.ZEOF=9Q°~35°=55°.bZBOE=180°-ZAOC-ZCOE=180°—35°—90°=55°,ZEOF=ZEOB,TᑖNBOF.ூ78௃9⚪ὃ=>dTᑖeḄfgj⚔dḄឋ.j⚔dl[dTᑖeḄfg(⚪ḄᐵC.24.᝞NOP7A,B,Cᦪ77CjAḄᦪ`6,BC=4,AB=\2.

13RCa1\7A,8jAḄᦪ;a2\7P,஺]A,CᑖS[¡¢6ᓫmr3ᓫmḄ¦§ᦪD&ᔣ©MAPḄ7NᙠCQ¬CN=C஺©L`জ7M,NjAḄᦪaᵨ®஺ḄK¯⊤±\ঝ`²³OM=2BN?ூ6ᫀ௃a1\AjAḄᦪ`-10,8jAḄᦪ`2a2\জM⊤±Ḅᦪ—10+37,N⊤±Ḅᦪ6+/2ঝ·1=18¢ᡈf=y¢OM=23N.ூ(᪆௃ூᑖ᪆௃a1\᪷7CjAḄᦪ`6,ᨵ஺C=6,᪷BO4,OB=OC-BC=6-4=2,ᓽ7B⊤±Ḅᦪ2᪷A5=12,OA=10,ᓽÀ⚪(a2\জ᪷7Pஹ஺©ᱯ7AP=6r,CQ=3t,᪷M`┐Ḅ7CN=CQ,AM=^AP=3t,CN=CQ=t,ᔠAjAḄᦪ`TO,C⊤±Ḅᦪ6,ᓽ(ঝ᪷a1\M,N⊤±Ḅᦪᓽ0"=|-10+310N=6+t,ᓽᨵBN=ON—OB=6+t—2=4+t,ᔠOM=2BN,È10+3r|=2a4+r\=8+2r,ᓽ6.À1,(௃•.•7CjAḄᦪ`6,A0C=6,BC=4,OB=OC-BC=6-4=2,.•.7B⊤±Ḅᦪ2,•/AB=12,.OA=AB-OB=l2-2=lO,᪷7Aᙠ07ÊË7A⊤±ḄᦪTO,ᓽ4jAḄᦪ`TO,BjAḄᦪ`2ூÀ2,(௃

14জ;7ஹ஺ᑖS]AஹCᑖS[¡¢6ᓫmr3ᓫmḄ¦LAP=6/CQ=3t,•..²`”Ḅ7NᙠC஺¬CN=C஺AM=ÍAP=3r,CN=%CQ=t,AjAḄᦪ`TO,C⊤±Ḅᦪ6,M⊤±Ḅᦪ10+3/,N⊤±Ḅᦪ6+ঝ••஻⊤±Ḅᦪ—l()+3f,/.OM=|-10+3f|,•••N⊤±Ḅᦪ6+r,ON=6+r,jAḄᦪ`2,.•.08=2,/.BN=ON-OB=6+t—2=4+t,•••OM=2BN,.•.|-10+3f|=2(4+f)=8+2r,·10+3/=8+2/,f=18,2·—10+3t=-(8+2f)Ò=Íᦑ·Ô=18¢ᡈf=|¢OM=23N.ூ78௃9⚪ὃ=>ᦪḄ7À⚪ஹᙠᦪ⊤±ᨵᳮᦪ[ᦪn7ÕLḄÖ×Pw஺0=È10+34(69⚪ḄᐵC.25.᝞N17஺`oeA37Ø7஺Ùe0C,ÚZBOC=12()°.ÝoddÞḄod⚔7ßᙠ7஺ᜐá0MᙠÙe0BâáONᙠoeḄ&.

15(1)ᙠN1ZAOC=NNOC=(2)ÝN1ḄdÞã7஺⌮┐åæçN2,ÚáQMᙠNBOCḄᑁè¬ាêTᑖZBOC.ÀHoeONᔲTᑖNAOC?VWᳮᵫ.(3)ÝN1ḄdÞã7஺ì┐åæçN3,ÚQNᙠNAOCḄᑁèজZCOM+ZNOAḄᦪঝZAOM-ZNOCḄᦪ.ூ6ᫀ௃(1)60150(2)oeQNTᑖNAOC,ᳮᵫ(᪆(3)জ150஺ঝ30஺ூ(᪆௃ூᑖ᪆௃(1)᪷NAOC+ZBOC=180°,NBOC=120°,ᓽNAOC=60°,᪷NACW+NM0N=180°,NMON=90°,ᓽN4ON=90°,ᑣNNOC(2)NOḄðñe`0஺᪷TᑖZBOC,NMOC=NMOB=òNBOC=60°,ᑣᨵ2ZCOD=900-ZMOC=30°,óôᨵNCOD=-ZAOC,ᑣoeONTᑖZAOC%2(3)জNOḄðñe`OE,ᐜNEOM=90°,$᪷/஺஺0+/77஺4=/஺஺0+/öᓽ(ঝ᪷ᩩøNAOM=90°-ZAON,ZNOC=600-ZAON,$᪷ZAOM-NNOC=(90஺-ZAON)-(60஺-ZAON)ᓽ6.ூÀ1,(௃VZAOC+ZBCC=180°,ZBOC=120°,ZAOC=180°-NBOC=60°,NAON+/MON=180°,ZMON=90a,/AON=90°,ZNOC=ZAON+ZAOC=900+60°=150°,ᦑ6ᫀ`60,15000ூÀ2,(௃oeONTᑖNAOC,ᳮᵫ᝞NOḄðñe`O஺᝞N

16•••TᑖZBOC,ZMOC=ZMOB=-NBOC=-xl20°=60°,22bZMOD=AMON=90°,ZCOD=90°-ZMOC=30°,•ZAOC=60°,NCOD'NAOC,2ᓽoeONTᑖNAOCூÀ3,(௃জNOḄðñe`OE,᝞NᑣN2VQ4=N£Q3,•%NMON=90°,ZEOM=90°,VZBOC=120°,.Z.COM+ZNOA=ZCOM+ZEOB=360°-ZMOE-ABOC=360°—90°-120°=150஺ᓽᡠú`150஺ঝ•NMON=5°,ZAOC=60°,

17/.ZAOM=900-ZAON,ZNOC=60°-ZAON.ZAOM-ZNOC=(90°-ZAON)—(60஺—ZAON)=30°.ᓽZAOM-ZNOC=30°.ூ78௃9⚪:⌕ὃ=>dTᑖeḄឋûᑨf[düÞḄdýþPw⚪ÿ
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18