2021-2022学年湖南省长沙市岳麓区八年级（上）第三次段考数学试卷（附答案详解）

《2021-2022学年湖南省长沙市岳麓区八年级（上）第三次段考数学试卷（附答案详解）》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

2021-2022
ᓭḕᙛ᪥
±ὃᦪᔁI.2020
"#$%&'()*+,-./.ᐰ1234▾66⌱849:ᕒ<=>?.@☢BC34▾᪗EḄGᫀIᑖᐸLBMNOGPḄBB./-I■=S\TU4▾DWXY4▾2.@ᑡ[\Bᑖ[ḄBA.-B.-+yC.2D—22ZX+l7T3.defBghijkᨬↈᓾoᨬpqḄrsᩞᧇ#vBwᵯឋᨬzḄᩞᧇ#ᐸᳮ|}~0.00000000034s#}~ᵨᦪ⊤A.0.34xIO-sB.34.0xIO-11sC.3.4x1()T°sD.3.4x10-9s4.ᑭᵨ[(3a+b)2()A.3a2+b2B.9a2+b2C.9a2+3ab4-b2D.9a2+6ab+b25.@ᑡḄB()A.3x2y+5yx2=8x2yB.2x-3x=6xC.(3*)3=9x9D.(—x)3•(—3%)=-3x46.᝞G#ᙠ¤¥BCL#AB=AC,Z.BAC=100°,ABḄᚖ¨©ᑖª£>Eᑖ®¯ABஹBCDஹE,ᑣNB/1E=()A.80°B.60°C.50°D.40°7.@ᑡᐵᑖ[·Ḅᔜ¹ºL#┯¼ḄBA.½x=0¾#ᑖ[¿ᨵÁÂB.½%>-2¾#ᑖ[ḄÃÄᦪC.½Å<-2¾#ᑖ[ḄÃᦪD.½Å=-2¾#ᑖ[ḄÃ08.ᙠὶᔠÉi#ᨵ4ஹ8ஹCÊ⌱ËÌᙠÍÎÏPḄÎ⚔ÑÒÓi#ÔÕᙠÖ×Ø\ÙÚ#⌕ÜᙠÔÕLÝÞÍÎᩈØ#àᐜ×ᑮØ\àãä#åÙÚ©,ᑣØ\æÞḄᨬ〉½ḄÒÓBᙠ¤48஺Ḅ

1A.éLªḄ¯ÑB.ᩩÏ©ᑖªḄ¯ÑC.éLᚖªḄ¯ÑD.éiëḄ¯Ñ9.ìíî+ï=2,nm=-2,ᑣ1+ml+òḄÃA.-3B.-1C.1D.510.ó᯼õöᑜxᜩùú120f᯼#ᵫýᵨ$Ḅᢈÿ
ᜩ332ᜩᡂᑡḄ120120120120AoDoD.---=-----3x-2xxx+2120120U.--=----3D.—=--3X+2Xxx-211.ᑖ7="Ḅ#$X-1X2-1A.%=1B.%=-1C.%=3D.12.᝞)᦮ᦪ஺-.ᐵ0xḄ234ᨵ#6-.ᐵ0*Ḅᑖ§---=-3ᨵ9᦮ᦪ#ᑣ;<ᩩ>Ḅᡠᨵ᦮ᦪ஺@Ax-33-xA.—3B.—2C.0D.113.F-2,3ᐵ0xHḄIJFḄᙶ᪗$.14.9NOPḄQRᑁT30144஺ᑣUNOP$9____OP.15.XYZ=3,4y=5,\Ij2*-2yḄ_.16.᝞aᙠRteABCf/.ACB=90°,AC=BC,BCOᙠ8CḄjkl3OABC஺FE8஺ḄfFFPCEoQpFqrAP,BP,sAP+BPḄ_ᨬvweCBPḄxᦪ.17.yz{|-3|+(-1)2013x(7T-3)°+(-2)2+V8.18.ᑖ#{(1)3/-18/+27X.(2)4a2(x-y)+b2(y—x).19.ᐜᓄ_{(1--Q)•2"஺ᐸfx=2.x-rxz-6x+920.#ᑖ{21.᝞a/BAD=4CAE=90஺AB=AD,AE=AC,AF1CB,ᚖ<F.1{SABC^^ADE$2N4EḄxᦪ.2⚓ᐳ16⚓

2E22.“ᙳ⊝ᦟᜧ”I¡¢£¤¥¦᪥ḄQ¨ᐰª1200«Ḅ⍝®¯°ᦋ⌼³´₝¶☢.³´400«¸°¹ºᡂ⍝ᦋ⌼¸ᩭ
ᜩḄ¼lᦔ᳛¿ÀyᑜÂ25%,r)ᐳᵨ13ᜩᡂ⍝ᦋ⌼ÄÅ.(1)Àyᑜ
ᜩ³´☢NÆ«Ç(2)ÈÉᒹᖪÀᩭ
ᜩÌͼμÏ1500ᐗ¼lᦔ᳛¸
ᜩÌÍѼÎḄ¼Ïª°20%,ᡂ᦮R¼¸ÉᒹᖪᐳÌͼμÏNÆᐗÒ23.XY{᝞a1,ᙠAABCf4஺$NB4CḄÓᑖÔ.E$Ô¨AOoQF(FE2ÕFA,F஺Öᔠ);

3(1)FBḄᙶ᪗Ç(2)᝞a1,pFCë
ì1RᓫîªxḄïxð஺FñòxHḄ9óHᔣõpöwpFAë
ì3RᓫîªxḄïxð஺FñòyHḄ9óHᔣõp´õpḄw÷fìstø_we4BC$ëA3ùOḄ3ῪÙTûTPÇ(3)᝞a2,ᙠ(2)Ḅᩩ>ülÛ4BCḄÓᑖÔ8஺´80ḄªឃAADBḄ☢þS.ØᵨÿmḄ
⊤S.4⚓ᐳ16⚓

4ᫀ᪆1.ூᫀ௃Aூ᪆௃ூᑖ᪆௃⚪ὃḄᭆḄᐵ!"#$%ᑖᢚ'()*ᔠ.᪷-Ḅᭆᔜ⌱⚗ᑖ᪆ᑨ2ᓽ)4.ூ௃5⌱⚗A6#ᑮ8᪵Ḅ:ᩩ<=>?:ᩩ<=ᢚ'<=$@Ḅ%ᑖ6ABC*ᔠᡠE!FG⌱⚗BஹCஹ஺J6#ᑮ8᪵Ḅ:ᩩ<=>?:ᩩ<=ᢚ'<=$@Ḅ%ᑖ6ABC*ᔠᡠEJ!FGᦑ⌱5A.2.ூᫀ௃Cூ᪆௃5AஹLMᦪᙠᑖPᦑQ⌱⚗J!ᑖ
Q⌱⚗JRᔠ⚪SG8ஹLMᦪᙠᑖPᦑQ⌱⚗J!ᑖ
Q⌱⚗JRᔠ⚪SGCஹLMᦪᙠᑖTPRᔠᑖ
ḄUVᦑQ⌱⚗!ᑖ
Q⌱⚗Rᔠ⚪SG஺ஹLMᦪᙠᑖPᦑQ⌱⚗J!ᑖ
Q⌱⚗JRᔠ⚪S.ᦑ⌱5C.᪷-ᑖ
ḄUVᓽ).⚪ὃᑖ
ḄUVWXᑖ
ḄUV!⚪Ḅᐵ.:Yᙢ᝞\A,B⊤$]᦮
_`8abᨵdTef
J(BKO)gFᑖ
hSᐔ!ᦪd.3.ூᫀ௃Cூ᪆௃:0.00000000034k,Qmnᵨpqrᦪs⊤t3.4x1஺:௃஺kᦑ⌱5C.uvwx1Ḅyᦪz)Eᑭᵨpqrᦪs⊤:Y
tax10-%|}ᜧᦪḄpqrᦪsJḄ!ᐸᡠ>ᵨḄ!ᢣᦪᢣᦪᵫᦪ:]JtḄᦪd☢Ḅ0Ḅ]ᦪᡠU.⚪ὃᵨpqrᦪs⊤}wḄᦪ:Y
taxIO',ᐸai<||

5⚪⌕ὃḄ!ᐰ
ḄᵨWX
!⚪Ḅᐵ.5.ூᫀ௃Aூ᪆௃5Aஹ3x2y+5yx2=8x2y,⌱⚗yRᔠ⚪SGBஹ2x-3x=6x2,ᦑ⌱⚗┯¢JRᔠ⚪S5Cஹ(3᮱)3=27%9,ᦑ⌱⚗┯¢JRᔠ⚪SGDஹ(-X)3•(-3x)=3x4,ᦑ⌱⚗┯¢,JRᔠ⚪SGᦑ⌱5A.᪷-ᔠ_±⚗sᑣஹᓫ⚗
´ᓫ⚗
Ḅµsᑣஹ¶Ḅ´sᑣᑨ2ᓽ).⚪ὃḄ!ᓫ⚗
´ᓫ⚗
ஹᔠ_±⚗ஹ¶Ḅ´ᓫ⚗
|ᓫ⚗
C´·¸¹ḄºᦪCdTᑖ»C´x¼ᙠ:]ᓫ⚗
½bᨵḄdTᑣ¾¿ḄᢣᦪÀt¶Ḅ:]Á
.6.ூᫀ௃Dூ᪆௃5-AB-AC,/.BAC=100°,•••NB=NC=(180°-100°)+2=40஺vDE!ABḄᚖ<ᑖ=•AE=BE,•&BAE-Z-B=40°,ᦑ⌱5D.✌ᐜᑭᵨÐÑḄᑁÑUᳮÔῪÐÑḄឋ×ZB,ᑭᵨ=Ùᚖ<ᑖ=Ḅឋ×᧕44E=BE,&BAE=LB.⚪⌕ὃÔῪÐÑḄឋ×ÐÑḄᑁÑUᳮ=Ùᚖ<ᑖ=Ḅឋ×WXᚖ<ᑖ=PÛS:Üᑮ=Ù$ÝÜḄÞßCÔÔÔÑ!à⚪Ḅᐵ.7.ூᫀ௃Bூ᪆௃5áâx=0ãᑖTt0,ᑖ
äᨵSVGyåJRᔠ⚪S.Bஹâ-2

6ூ᪆௃5•••ÐÑḄÐᩩᚖ<ᑖ=ḄñÜᑮÐÑᔜ⚔ÜḄÞßCÔ•••óôᙠõ4BCḄÐᩩᚖ<ᑖ=ḄñÜᨬ〉â.ᦑ⌱5C.t>øù⌕>óᑮÐ]áḄÞßCÔx!ᑭᵨ=Ùᚖ<ᑖ=PḄÜᑮ=Ù$ÝḄÞßCÔ)M⌕ôᙠÐaᚖ=ḄñÜP.⚪⌕ὃ=Ùᚖ<ᑖ=Ḅឋ×ḄᵨGᑭᵨᡠqḄᦪqMúû▭ý⚪!:þ6ÿ⌕.ᑮ⌕ᑮḄ⚪Ḅᐵ.9.ூᫀ௃Cூ᪆௃!■-m+n=2,mn=—2,■■(1+m)(l+n)=l+n+m+mn=1+2-2=1.ᦑ⌱!C.᪷()⚗+,-)⚗+Ḅ.ᑣ0⊤23(1+m)(l+n)=1+n+m+nrn,45ᐭ78ᓽ0.⚪:⌕ὃ<)⚗+,-)⚗+=>)⚗+,-)⚗+Ḅ.ᑣ⚪Ḅᐵ.?⌕@⚗@ABᨵDE⚗ḄᔠGDE⚗.10.ூᫀ௃Dூ᪆௃ூᑖ᪆௃⚪ὃ<ᵫJ▭L⚪MNOᑖ+PQᐵROᜩᦪ-UVᦔ᳛V3YᐵZᑡPQ.R\7ᑜxᜩ^_120f᯼ᑣJ▭(x-2)ᜩ^_120f᯼YᐵZ3!\7ᑜUVᦔ᳛=J▭UVᦔ᳛-3,bc0ᑡOPQ.ூ௃!R\7ᑜxᜩ^_120f᯼ᑣJ▭(x-2)ᜩ^_120/᯼᪷(⚪d-=^-3.xx-2ᦑ⌱D.11.ூᫀ௃Dூ᪆௃!PQefD,-/h1,dx+1=2,dx=1.ijk!x=l\PQḄl᪷\PQm.ᦑ⌱!D.⚪ὃ<ᑖ+PQḄnopqPQ0dᨬstᑖB!x2-l,efDu,ᨬstᑖB0vᑖ+PQᓄ3᦮+PQᩭ.⚪ὃ

7(2)ᑖ+PQh⌕k᪷.12.ூᫀ௃Dூ᪆௃!?+;••?+ᨵA3a—4<%<2+a,3a-442+a,d!aS3,ᑖ+PQ9—--=-3d!x-33-xX=~H3)fl+3•••a3᦮ᦪᑖ+PQ—=-3ᨵ᦮ᦪx-33-x••.aḄ3!3,0,-2,3+0+(-2)=1,ᓽᩩḄᡠᨵ᦮ᦪ஻¢£31,ᦑ⌱!D.?+¤¥j?_4,᪷(“?+ᨵ”dᑮᐵ©஻Ḅhᐗh«?+,¢ᑖ+PQ-2=-3,᪷(“஺3᦮ᦪᑖ+PQ---=-3ᨵ᦮x-33-xx-33-xᦪ”®O¯ᔠᩩḄ”Ḅ°±ᓽ0dᑮᫀ.⚪ὃᑖ+PQḄP.£hᐗh«?+P.⚪Ḅᐵ.13.ூᫀ௃(h2,-3)ூ᪆௃!²(h2,3)ᐵ©x´Ḅµ¶²Ḅᙶ᪗(-2,-3).ᦑᫀ3!(-2,-3).᪷(''ᐵ©x´µ¶Ḅ²ºᙶ᪗D»ᙶ᪗¼3½ᦪ”.⚪ὃÁµ¶²Ḅᙶ᪗ÂÃ!(1)ᐵ©x´µ¶Ḅ²ºᙶ᪗D»ᙶ᪗¼3½ᦪ¥(2)ᐵ©y´µ¶Ḅ²»ᙶ᪗Dºᙶ᪗¼3½ᦪ.14.ூᫀ௃ᓝூ᪆௃!R)fÅ஻fÅᵫ⚪d(n-2)x180°=144°Éd71=10,ᦑᫀ3!ᓝ.᪷()fÅḄËᑁÍ0d)fÅḄᑁÍ£4᪷()fÅḄᑁÍ£t+,Î8⚓ᐳ16⚓

80dᫀ.⚪ὃ

9ூ᪆௃-1Ḅ᜻«P3-1,øùᦪḄ0«Pᙳ31,ᵫcÞß78ᓽ0.⚪ὃ

1021.ூjᫀ௃l(1)^^BAD=^CAE=90°,•^BAC+CAD=90°,Z-CAD+^LDAE=90°,:.Z.BAC=Z.DAE,ᙠB/CgDAEAB=AD(BAC=/-DAEJAC=AE•••8ACWZME(S/S)(2)vZ-CAE=90°,AC=AEf•E=45°,ᵫপZ.BCA=NE=45°,♦AF±BC,•ACFA=90°,•Z.CAF=45°,•Z.FAE=/.FAC+Z-CAE=450+90°=135°.ூ᪆௃3⚪ὃ&'ᐰḄᑨgឋḄឋ01ᐰḄᑨᳮ23⚪Ḅᐵ5.(1)᪷⚪g⚪Ḅᩩ¡ABCW4DEḄᩩ(2)᪷পḄ¢£gῪḄ¥oᑮ4¦4EḄ§ᦪ.22.ூjᫀ௃(1)l©Qᑜ«ᜩ©®☢x¯᪷⚪ol4001200-400------1-----------------=13x(14-25%)xolx=80stlx=802xḄ°±ᔠ⚪jlQᑜ«ᜩ©®☢80¯ᩭ³´400+80=5(ᜩ)(2)!ᩭ³´(1200-400)+[80x(l+20%)]=8(ᜩ).ᐳµ¶³·³¸l1500x5+1500x(1+20%)x8=21900(ᐗ)jlᐳµ¶³·³¸21900ᐗ.ூ᪆௃(1)©Qᑜ«ᜩ©x¯º⍝¼³´ᦔ᳛¿!«ᜩ©(l+25%)x¯º⍝᪷ᐳᵨ13ᜩᡂÁÂÃÄᑡxjᓽ.(2)᪷(1)ᦪWᐭjᓽ.3⚪ὃ&'ᵫÆ▭È⚪ÉÊᑖxj3⚪Ḅᐵ52ËÌ⚪©Íᦪ¡ᔠ〉ḄÏᐵÐᑡx.

1123.ூjᫀ௃36126ூ᪆௃(1)lE4=EC,•ACAE=Z.ACE=18°,♦DEC=Z.CAE+Z.ACE=36°,vAABE=2Z.ACE,AACE=18°,•Z,ABE=36°,4D2NB4cḄᑖÑ♦BAE=Z.CAE=18°,Z.AEB=180°-Z-BAE-ABE=180°-18°-36°=126°,ᦑjᫀ2l/-DEC=36°,Z.AEB=126°(2)l᝞Ô1,Ô1ᙠACÕÖ49=AB,×Ø᪶,•••4஺2484cḄᑖÑ,BAE=Z-CAEjvAE=AE,••.4EF4EB(S4S),EF=EB,Z-AFE=Z.ABE,vZ-ABE=2Z-ACE,:.Z.AFE=2/-ACE,vZ-AFE=Z.ACE+CEF,•2/.ACE=/-ACE+CEF,:./.ACE=CEF,•EF=FC,•FC=BE,••AC=/F+FC=/B+8E(3)l᝞Ô2,Ô212⚓ᐳ16⚓

12^Z-CAE=^BAE=a,&ACE=0,AZ-ABE=2᜛•&DEB=Z-BAE+/.ABE=a+2£,vBE=BD,Z-ADB—&DEB=a+20,vÜ408=Z.CAE+Z.ACD,•2᜛=a+{Z-ACE+&DCE),:.2£=a+(᜛+Z.ACD),•Z,ACD=0,:.Z-ACB=2/-ACE=Z-ABE,•CE2ZACBḄᑖÑ4D2Ü&4BḄᑖÑEÞ4BCḄᑁß•Z.ABC=Z.ABE—2/7,•/.ABC=2Z-ABEfᙠ4BCZ.BAC+/.ABC+Z.ACB=180°,ABAC+2Z.ABE+Z.ABE=180°,3AABE+Z.BAC=180°.(1)ᵫà4=EC^Z-CAE=/.ACE=18°,NáYo¢â(2)ᙠACÕÖAF=AB,×Ø/E,oBAEgA4FE,äá4AFE=4ABE,᪷N4BE=244CEoCEF2ῪNÂåo(3)ᐜæ4DEC=44CE,äáoE2ABCḄᑁßNáBEᑖÜ4BC,᪷ᑁgæg484cḄᦪÏᐵÐ.3⚪ὃ&'ῪឋᐰᑨgឋᑁßçèÈ⚪Ḅᐵ52“Öê⊡ì”îᑁßḄឋ.24.ூjᫀ௃(1,3)ூ᪆௃l(1)DQ=-1,b=6,஽=3F-1+?=1,3x(—1)+6=3,••ÞP(-l,6)Ḅ“3ÐñᙛÞ"P'Ḅᙶ᪗y(1,3),ᦑjᫀyl(1,3)(2).Þ2(ö0),%y÷᦮ᦪÞøḄ'஻ÐñᙛÞ”yP'Þ•P\x,kx),:.PPr=Jo+(kx)2=\kx\,OP=x,A\kx\+%+2k=7,B|Jfcx+%+2k=7ᡈ-kx+%+2k=7,

13oleüᡈý•••ky÷᦮ᦪ•••k=2ᡈ6(3)þᑖxÿ
(-3)(%+3),mx2+(12+3ni)x+36=0,•ᑖ•••x2-9=0,ᓽx=3ᡈx=-3,জx=3ᐭ+(12+3m)x+36=0,ᑣ?n=-4ঝx=-3ᐭn/+(12+3m)x+36=0,ᑣ9m—36—9m+36=0(ᔠ⚪5,!")$m=-4.(1)᪷&'P'('PḄ*+ᙛ'”Ḅ./01(2)᪷&'P'('2Ḅ"2*+ᙛ'”Ḅ./3P''ᙶ᪗6᪷&7'8Ḅ9:;3PP'.(3)ᑖ"ᑖ@Aᓄ(᦮ᵫᑖ=3xḄEᐭ᦮Ḅ=3mḄEᓽ>.F⚪ὃHI7'8Ḅ9:;ᑖḄJK'P'('PḄ“*+ᙛ'”Ḅ./ஹḄNO⚪ḄᐵQ.25.ூSᫀ௃V(1)a2-8a+16+\b-l\=0,•••(a-4)2+|b-l|=0,W("4)220,|6-1|20,**.CL—4=0,b—1=0,•Q=4,b=1,8(4,1)Z1•••8(4,1),BH=1,ᵫ⚪[஺4=3t,OC=t,]14⚓ᐳ16⚓

14`4cBOA3aḄbῪdefeg:.AC=BC,&ACB=90°,,ZCO+4BCH=90°,•BH1%i&OHB=90°,:.&BCH+&CBH=90°,2LAC0=&CBH,•j40c=Z.CHB=90°,ᙠAAOC8ACHB9,(Z.AOC=Z.CHBj^ACO=&CBH,14c=CB*.AAOCdCHB(AAS),OC=BH=1,•t=1,•t=l`ABCOAB(aḄbῪdefeg(3)k'AlAF1DB,m3஺nopq2A2nopmḄnopq'£•/.AFB=&ACB=90°,AZ1+ZF=9O°,Z2+ZE=9O°,z.2=zl,ᙠADCBt`£10!u22=Z1AC=BC,Z.DCB=Z.ECA=90°•.AE=DB=m,ᙠvBFA^^,BFEu22=Z3BF=BF,^BFA=&BFE=90°.ABFA^^BFE(ASA^

1511AF=EF=-AE=-m,22•••S=--BD-AF=-xmx-m=-m2.2224ூ᪆௃(1)᪷&yzឋ3”஻ḄE}~Sᓽ>(2)kBl1xiqH,᪷&bῪdefegḄឋ<ᐰbfegḄᑨ.<ឋSᓽ>(3)k'Al/Fm80nopqAFnopm8cḄnopq'E.᪷&ᐰbfegḄᑨ.<ឋSᓽ>.F⚪Ofeg$ᔠ⚪ὃHIᐰbfegḄᑨ.tឋஹbῪdefegḄᑨ.tឋbF⚪$ᔠឋᨵ.fegᐰbO⚪ḄᐵQ.]16⚓ᐳ16⚓