2021-2022学年河南省南阳市多校八年级（下）期末数学模拟试卷（附答案详解）

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2021-2022
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319.᝞Dûᦪü=ýþḄDp[ÿ
ᦪy=0">°)ḄC(6ᙶ᪗1ḄPᙠ
ᦪஹ=B஺>0)Ḅ$%ᨵ'()/+,P,C.(1)-1=»2—.(2)/()/Ḅᦪ⊤123(3)5()/6y74,:()0C;<)CP=ᔣ?@AAᜐDEF/G()0Cᙠ?@,HI6x7Ḅᙶ᪗ḄKLN.20.᝞ᙠQRABCOI”UVA஺ḄIPUVBC$ḄWPE1MC,PF1BM,ᚖYE,F.(1)[QRA8CDḄ^6_`YabᩩdefVRPEMFQRijklḄmn3(2)᝞ofVRPEMFQRpb[PqWᑮabsteQRPEMFuv=RiwjklḄxyᔩi4MDBPC21.{|Ḅ}ᝍ☘|Ḅ“”W+.qWᘤᩞᖪḄᜮᡂ├ᖪ.ᜮḄ¡¢50ᐗᖪᵨ4000ᐗ¦Ḅᜮ6ᵨ3000ᐗ¦Ḅᦪ§'᪵©.(1)/ᜮḄ¡3(2)ªᖪ«ᑜ¦ᜮᐳ200®Ḅᦪ§¯ᜮḄ2°.¦±ᢥ¢¡18%´¡ᜮᢥ¢¡15%´¡.Ꮇ5ªᖪ¦Ḅ¶·¸ᖪᨬ±ᙳwᢥ´¡»GFl/Gªᖪw¼½ᨬᜧᑭÀḄÁ=ᫀ.22.ᵬஹÄ·ÅÆÇÈÉAᙢGËᵬᐜGË8Íe±ÄÎGËÄÏÐ6ÍeÑÒ$ᵬ[ÄÑÒ$ᵬ±ÄÓᓽÕÖAᙢ(ÄᣵᜮḄeØÙᶍ¯«)ᵬÛÜᔣ8ᙢÝÏÄÕÖAᙢDEeᵬÞ8ᙢßᨵ3ÍeḄàHᙠ᦮®ÆÇ,HIâ4⚓ᐳ20⚓

4ᵬÄᙳäᢝᔜçḄèéᒴèÝᵬஹÄ·ÅôõḄàHy(ᓟò)6ᵬGËḄeØx(Íe)ëØḄᐵí᝞ᡠïð(1)/ᵬஹÄ·ÅÆÇèéi(2)4ஹB·ᙢàHU©ᓟòi(3)ᙠ᦮®qW,HIxóLeᵬஹ23.ᙠV^5Ḅv=RA8C஺IEᙠVC஺ᡠᙠ()$ö÷BE,BE,ᙠBEḄø=ùv=RBEFG,úö÷4G.(1)᝞1,[E6஺ûᔠeAG=3(2)᝞2,[Eᙠ)ý8$eDE=2,/AGḄ^;(3)ÿ4G=ᑏOEḄ.

5ᫀ᪆1.ூᫀ௃Cூ᪆௃-5H0,***xᱏ5.ᦑ⌱C.᪷#ᑖ%ᨵ'(Ḅᩩ*ᑖ+,-.0ᓽ01ᫀ.2⚪ὃ56ᑖ%ᨵ'(Ḅᩩ*78ᑖ%ᨵ'(Ḅᩩ*ᑖ+,-.09⚪Ḅᐵ;.2.ூᫀ௃Bூ᪆௃=x=1,y=m?ᐭy=2x,1m=2.ᦑ⌱B.ᵨ?ᐭCᓽ0.DEFᙠHᦪJKLᑣNFḄOஹQᙶ᪗TUHᦪ᪆%.3.ூᫀ௃Cூ᪆௃120nm=120x10-9m=1.20x102x1YT9=0x10-7m.nl12ᦑ⌱C.\]^_.1Ḅ`ᦪa0bᑭᵨdefᦪC⊤hEij%kax10-%noᜧᦪḄdefᦪC,qḄ9ᐸᡠtᵨḄ9u᦮ᦪᢣᦪxᢣᦪᵫzᦪ{|}~E,kḄᦪ☢Ḅ0Ḅᦪᡠ.2⚪ὃ5ᵨdefᦪC⊤ho_ḄᦪEij%kaxlO-%ᐸ14|10,஻kᵫzᦪ{|}~E,kḄᦪ☢Ḅ0Ḅᦪᡠ.4.ூᫀ௃Aூ᪆௃ᵫ014஺=CO,BO=DO,ᡠb|jABC஺9|j#9]ᑖḄ|j9|j.ᦑ⌱A.4CBD9]ᔜFᑣ]ᑖYᓽ4஺=OC,8஺=஺0Ḅ|j9|j.2⚪¡⌕ὃ56|jḄᑨ¤f|jḄᑨ¥C9⚪Ḅᐵ;.5.ூᫀ௃Bூ᪆௃⌕6¦§¨©ᨬᵹ├®¯°¦§¨©±Ḅᨬ²³ᐵ´µᦪᦑ⌱B.~6⚓ᐳ20⚓

6⌕6¦§¨©ᨬᵹ├¯⌕ᐵ´¦§¨©±Ḅᨬ²¸¹ºᦪᨬ²Ḅᦪ³ᐵ´µᦪ.ὃ5ᙳᦪஹµᦪஹ¼ᦪஹ¥½Ḅ'(ᱯFᳮᔜÀÁÂḄᱯF9Ã⚪Ḅᐵ;.6.ூᫀ௃Bூ᪆௃AஹÄ4B=C0,4CJ.B஺|jABC஺,9|jÅᦑ⌱⚗A,Çᔠ⚪'ÅBஹ■$AB//CD,AB=CD,|jABCD9|jvAC1BD,|jABCZkÉjᦑ⌱⚗BÇᔠ⚪'ÅCஹÄᨴC=BD,4clBD|jABC஺,9|jÅᦑ⌱⚗C,Çᔠ⚪'ÅDஹÄË4BC=4DCB|jA8C஺,9|jÅᦑ⌱⚗஺,Çᔠ⚪'.ᦑ⌱B.᪷#ÉjḄᑨ¥CᑖÌ]ᔜ⌱⚗Íᑨᓽ01ÎÏ.2⚪ὃ56|jḄឋÑஹÉjḄᑨ-Ò⚪Ḅᐵ;9¤Ó78ÉjḄᑨ¥CÔ.ὃÕὃ⚪¨.7.ூᫀ௃Dூ᪆௃•••×j0A8Ḅ☢Øk3,•Ù|=3,•••k=6ᡈk=—6,Ä஽=6-2x-3=6,³⌱⚗஺Çᔠ⚪'ᦑ⌱D.᪷#×jOABḄ☢Øk3,01kḄ^Ü᪷#JKLḄFQOᙶ᪗ḄØ-.k,ÍÝÞᓽ01ᫀ.2⚪ὃ56ßàáHᦪJKLFḄᙶ᪗ᱯâᳮßàáHᦪ&Ḅäå'(9`æḄᐵ;.8.ூᫀ௃Cூ᪆௃••ᐵ.xḄ¥çè=2Ḅ9uᦪ2X+1••x=m—2,ᑣm—2<0,1m<2,

7é12x+1W0,ᓽ2(?n-2)+1WO,1mH|ᦑ?n<2ðmHj.ᦑ⌱C.,-%Íòᑭᵨ,<01ᫀÜᑭᵨᑖ%ᨵ'(Ḅᩩ*1ᫀ.⚪¡⌕ὃ56ᑖ%¥çḄ`æ78ᑖ%¥çḄ¥C9⚪ᐵ;.9.ூᫀ௃Dூ᪆௃x>0,)/>0ð—2+ö=÷—xyx-y-y+x2----=---xyx-yᑣ2xy=(x-y)2,xyLyx_%2+y2xy(%—y)2+2xy—xy2xy+2xy=~xy-=4.ᦑ⌱D.]ᩩ*Í᦮ᳮ12xy=(x-y)2,Ü]ᡠøḄ%ùÍ᦮ᳮ?ᐭúḄ^ûüᓽ0.2⚪¡⌕ὃ5ᑖ%Ḅᓄþø^Ḅᐵ;9]úḄûüCᑣḄ78.10.ூᫀ௃Aூ᪆௃ÄF”ᙠA8᝞ᡠ,vAH=xtcm,:•S»AF=\AF-AH=Extern2-,☢ḼḄᜧᜧ;ᙠ8c᝞ᡠHPA/MFḄ$%HP=48,(8⚓ᐳ20⚓

8H•••SAHAF=\AF-AB,☢+,;ᙠCO᝞ᡠ“PḄ$CஹDஹPᐳ.,•••SAH"=^AF$P”$/Cᑮ஺23"P⌲567☢+867;ᙠOE᝞ᡠ“P9HAFḄ$%HP=EF,■'S^=\AF-EF,☢+,;AFᙠHF᝞ᡠ$•SAHAF=AF•FH,2H32ஹEᑮ2F56,”;⌲567☢+867<=0>?᯿2,AB0WtS5ᙠABSAHAF=4xt=4-5x=20x=40cm2,•1•x=2,জDE>5sts8HᙠBC☢+,.••”/BᑮC23ᵨI8-5=3s,•••BC=2x3=6cm,ঝ┯L>8WtW12஻ᙠCD☢⌲567,•••”/Cᑮ஺23ᵨI12-8=4s,;CD=2x4=8cm,

9•EF=AB-CD=10—8=2cm,ᙠ஺Ḅ$NEbOPᓽHP=EF,•••S=^AF,EF='x8x2=8cm2,ঞDE>hHAF12StSb”ᙠ஺E:.DE=AF—BC=8—6=2cm,•••”/஺ᑮE23ᵨI2+2=1s,Sb=12+1=13,ট┯L>H4FḄ☢I30cm2”ᙠABᡈ8”ᙠ43S^=4xt=8t=30cm2,VBt=3.75,HAFᙠCOS=^AF-HP=^x8xHP=30cm2,VBHP=7.5,hHAFCH=AB-HP=10-7.5=2.5cm,••/Cᑮ//23ᵨI2.5+2=1.25s,/AᑮC23ᵨI8s,ᐳᵨ8+1.25=9.25s,ঠ┯L>XDEḄᨵ2Zᦑ⌱]A.ᐜ᪷`”Ḅ23BaHᙠ+bcaHAFḄ☢,ᓄe?f2BaOᐵcḄchᨬjklmnᑨ8ᔜZqr.s⚪3uᦪḄwx⚪ὃz{Ḅ☢|}uᦪwḄឋᳮVuᦪwḄ⊤ḄVs⚪Ḅᐵ.11.ூᫀ௃-9ூV᪆௃V]}=8-1=—9,ᦑᫀI]—9.ᐜ}2n6r2n.s⚪ὃz{ᦪḄs2nV⚪ᐵᙠḄDEḄmnr.12.ூᫀ௃ூV᪆௃V]•.•4(3,%)$8(1)2)ᙳᙠuᦪy=WḄw%<2$•••4(-3,%)ᙠ(⌱⚗B(l,y2)(w▲•1—3m>0,
•m<-,3ᦑᫀI]7TI<1.᪷`uᦪwḄᙶ᪗ᱯ¤ᓽAᑨ84(-3,%)ᙠ(⌱⚗8(l,yz)(w▲Ba13¥>0,ᓽA§a"?Ḅª«.(10⚓ᐳ20⚓

10s⚪ὃz{uᦪḄឋ®¯uᦪḄ6ឋN°ᦪ±Ḅᐵ°V⚪Ḅᐵ.13.ூᫀ௃88.8ூV᪆௃V]ᵫ⚪ᑣ´µὃ¶ḄXᔠᡂ¹I]92x40%+85x40%+90X20%=36.8+34+18=88.8(ᑖ).ᦑᫀI]88.8.᪷`ᩗ½ᙳᦪḄmnr§«ᓽA.s⚪ὃz{ᩗ½ᙳᦪ.ᩗ½ᙳᦪḄnrVs⚪Ḅᐵ.14.ூᫀ௃96ூV᪆௃V]•••¾ABCQᕜhI40,?.BD=12,AB=BC=CD=AD=10,OB=OD=-BD=6,OA=OC,AC1BD,2•••
AOB=90",•••OA=y/OA2—OB2=V102—62=8.AC=20A=16,S¾ABCD=,BD=wx16x12=96,ᦑᫀI]96.ᵫ¾ḄឋB4B=BC=CD=AD=10,OB=OD=^BD=6,OA=OC,AC1BD,ᵫÀÁÂᳮB஺4=8,ᑣAC=2CM=16,ᯠjᵫ¾Ḅ☢|}§VᓽA.s⚪ὃz{¾ḄឋÀÁÂᳮ¾Ḅ☢|}PÄÅ>®¯¾Ḅឋ§aOAḄhV⚪Ḅᐵ.15.ூᫀ௃Æ0)ᡈ(9,0)8ூV᪆௃V]᝞A5IcÇcA8NM¾•,<.y=-1È+3NxÊஹyÊᑖËOÌAஹB,•4(4,0),B(0,3),•OA=4,OB=3,

112222AAB=\JOA+OB=V4+3=5,:.AM=AB=5,:.OM=9,•Mᙶ᪗(9,0)>᝞஺8I?.ÇcAM8N¾,vAM=BM,BM=4-%,ᙠRtZkOBMÝBM2=OM2+0B2BP(4-x)2=32+%2fVBx=Zo7Sà0)XᡠáâA,B,M,NI⚔ḄÇc¾äåæçᩩéḄMḄᙶ᪗(J஺)ᡈO(9,0).ᑖëìíîïজA5IcঝABI?.ᑖ˧aMᙶ᪗ᓽA.s⚪ὃzðuᦪwḄᙶ᪗ᱯ¤¾ḄឋPÄÅV⚪Ḅᐵñòᑖóîïô+õöV÷Ýὃøὃ⚪ù.16.ூᫀ௃V](1)ü+3=2.ëcb(x-3),ýþᑖÿ
2-x+3(x-3)=-l,
x=3.x=3x—3=0,%=3Ḅ᪷.m2+2mm2—1(2)(2+47n+4+Dm2—mm(m+2)m(m—1)[(m+2)2+1](m4-l)(m—1)mm~+2+Dm+12(m+1)mm4-2m+12mm+2'+12⚓ᐳ20⚓

12'•m—2,-1,0.1,m=2/=%=1.2+2ூ᪆௃(1)᪷3ᑖ/Ḅ56789ᓽ;<(2)ᱯ>?ᑖ/Ḅ@AḄBCDᑣFᑖ/78ᓄHIJᔠᑖ/LḄᑖMNOP0,⌱Rᔠ〉ḄTUᐭBCᓽ;.W⚪Y⌕ὃ\ᑖ/ᑖ/ḄᓄH9T]Ḅᐵ_F@AḄBCDᑣḄ`a.17.ூ]ᫀ௃7,888ூ᪆௃(1)••efḄᡂh7.8ijkl3mjkḄmᦪᨬpᑣefqrᡂhḄsᦪ7,8<᪍uḄqrᡂh8jkl3mjkḄmᦪᨬpᑣ᪍uqrᡂhḄsᦪ8<᪍uḄqrᡂhvwᑮᜧ᣸ᑡP3,4,5,6,8,8,8,9,9,10,ᨬL~Ḅᦪ8,8,ᑣLᦪ=8<ᙳᦪ(ᓫ)Lᦪ(ᓫ)sᦪ(ᓫ)ef777,8᪍u788ᦑ]ᫀP7,8<8<8<(2)efqrᡂhḄP2X[2X(5-77+(6-77+3X(7-77+3x(8-7)2+(9-7)2]=1.6<᪍uqrᡂhḄP2x[(3-7)24-(4-7)2+(5-7)2+(6-7)2+3x(8-7)2+2x(9-7)2+(10-7)2]=5<(3)efḄqrᡂhᳮᵫef.᪍uḄqrᡂhḄᙳᦪ᪵efḄwwᡂh.(]ᫀNᔠᳮᓽ;).(1)᪷3Lᦪ.sᦪḄ9ᓽ;<(2)᪷3/9ᓽ;<(3)᪷3Ḅwᦪ3ᓽ;
j]ᫀ.⚪ὃ\lᢚ.¡¢vL
ᑮ£⌕Ḅ¤¥¦§⚪Ḅᐵ_.¨ὃ\lLᦪஹsᦪ.Ḅ.18.ூ]ᫀ௃জᡈঝᡈঞজᡈঝᡈঞூ᪆௃(1)⌱®Ḅᩩ°Ḅ±²জᡈঝᡈঞᦑ]ᫀPজᡈঝᡈঞ<(2)³´⌱®জ

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OE=OF,µ¶·஺“¼8µ¶·.(1)ᵫ⚪ᓽ;
jJ½<(2)⌱®জ³ABAE¾ºDCF(SAS),ᓽ;
jJ½<⌱®ঝ³µ¶·QE8F8µ¶·ᓽ;
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jJ½<(3)ᵫ8µ¶·Ḅᑨᓽ;
jJ½.W⚪ὃ\l8µ¶·ḄᑨᵫឋÁஹᐰÃÄ·ḄᑨÅឋÁÆÇÈÉ`a8µ¶·ḄᑨÅឋÁ⚪Ḅᐵ_.19.ூ]ᫀ௃Ê3ூ᪆௃পÌC(6,<)Uᐭy=k1gy="
<=6Î,<=Ï2X226
Ð=&k=3.2+14⚓ᐳ20⚓

14ᦑ]ᫀPM3)(2)ᵫ(1);
ÑÒÓÔᦪḄ⊤Ö/Py=Ìx=1Uᐭy=
y=3.P(l,3),×ØIḄÔᦪ⊤Ö/Py=mx+n,ÌP(l,3),C(6,ÙUᐭ
„/(m=--
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