2021-2022学年辽宁省大石桥市周家镇中考联考数学试卷含解析及点睛

《2021-2022学年辽宁省大石桥市周家镇中考联考数学试卷含解析及点睛》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。

2021-2022ὃᦪᔁὃ1.⚪ὃஹஹஹὃஹᑏᙠᔁᑁ!ᙠᔁ"#$%᪗'஺2.)*+ᑖ⌱.⚪/0⚪⌱1ᫀ3◤ᫀᑏᙠᔁᢣ6Ḅ8ᑁ)9+ᑖ:⌱.⚪ᫀᑏᙠᔁ⚪;ᢣ6Ḅ<"஺3.ὃ=>?@⚪ᓱḄ᦮C஺ὃDE3FᔁG⚪ᓱ*HIJ஺*ஹ⌱.⚪KFᜧ⚪ᐳ12N0⚪/0⚪4ᑖᐳ48ᑖ.ᙠ/0⚪P1ḄQN⌱⚗Sᨵ*⚗UVᔠ⚪;⌕YḄ.Z1.᝞\]^ᦪ_"Ḅ`AஹB⊤bḄcᦪᑖdea,b,fghᑡjkᡂmḄUKZB0AA.|a+b|=a-bB.|a+b|=-a-bC.|a+b|=b-aD.|a+b|=a+b22.]^`Pa,m
,Qb,n
nᙠopqrᦪs=——Ḅ\v"waVOVb,ᑣhᑡDy*6z{ḄUKZXA.m+n<0B.m+n>0C.mn3.)24}~ᝍ2022ᙠᓅG~ᝍḄ⚗;ᨵK᝞ஹஹᓫjZஹK᝞⍝ஹஹ᪵jZஹᳫஹj.᝞\ᨵ5ஹᜧ0ஹᙢᙳ¡Ḅᓱᱏz☢ᑖdᓺᨵஹஹᳫஹᓫஹ¥¦¡Ḅ\ᫀ§☢¨ᐰ¡.ª«5ᓱᱏ¬ᒴ3z☢ᔣh¯ᙠ°±",³´µ¶·*¶1Ḅᓱᱏz☢ា¹U⚗;\ᫀḄᭆ᳛UKZ
M*12]_3A.-B.-C.D.-55254.¼12ᨴ24¾ᐰ¿ᜧÀᨵ1230000ÁÂÃẆÅÆὃ,1230000«NᦪᵨÈ'ᦪÉ⊤beKZA.1.23X106B.1.23X107C.0.123X107D.12.3X1055.ᙊ┵ḄÌ☢ÍÎU80cm,ÏÐ90c%,ᑣÑḄÒ☢ÓUA.360^cm2B.120ᐔcm1C.18OO^cm2D.3600ÔK7Ã26.¥NÕÖᳫḄ×KᓫØZᑖdU+5ஹ-3.5ஹ+0.7ஹ-2.5ஹ-0.6,zᦪ⊤bÙÚ᪗Û×ḄØᦪÜᦪ⊤bÝ᪗Û×ḄØᦪ.Þ³ßàḄáâᨬäå᪗ÛḄÖᳫḄ×UKZA.-2.5B.-0.6C.+0.7D.+57.æçè⌕éê1000ëḄì⍝íᙠὃîï◤ðç2ᜩ/ᜩ⌕pòóᑜõæç30ëö÷ᢥù¨ᡂ$ú.êòóᑜ/ᜩæçxëᡠᑡüýz{ḄUKZ

11000100010001000A,-----------------=2B.-----------------=2xx+30x+30xߟ1000100010001000C.------------------=2D.------------------=2xx-30%—30x8.᝞ᡧḄḄᡧ“ᡧ”."5Ḅ“ᡧ”#ᡂᙊ┵ᑣᙊ┵Ḅ(☢*
2525A.B.nC.50D.507r229.᝞+⁂-./0ᛞPḄᓭ3470஺6ᔣḄMᜐ9:;<40-=Ḅ>ᔣ?ᓅ6ᔣAB2;0C.ab>QD.—<0a11.᝞+cdeKᦪy=Kx>0
Ḅ+RSTfOABCghiḄjkM,ᑖmABஹBCjkDஹE,IXx12.Mnoᙢ◫rstuv᪥xyᣎ{|}~1
40tu*᩽F."ᣎ{ᦪᑴᡂ⚣ᦪᑖ6+᝞+ᡠᑣᣎ{ᦪᙠ5.56.5mḄ⚣᳛`

2þI
ÿ40
ᣎᦪ?⚣ᦪᑖA.0.1B.0.2C.0.3D.0.4ஹ⚪ᜧ⚪ᐳ6⚪⚪4ᑖᐳ24ᑖ.13.᝞ᙠRtAABC#ZA=90°,AB=AC,BC=&+L$M,Nᑖ%&'BC,AB(Ḅ*$+MNᡠᙠḄ-ᢚ/NB,0$BḄ12$3456ᙠ'AC(78MB
C9:;:<ᑣBMḄ>914.᝞ᡠ?,ABC'10
,ᑣ2ἠ9____ᐗ.ᵨaḄ¡⊤?

317.£ᑖ¤a2b+2ab+b=.18.¥NO¦§¨©“*”a*b=-a--b,ᑣx*2=l*xḄ¤9.34;ஹ¤®⚪ᜧ⚪ᐳ9⚪ᐳ78ᑖ¤®2ᑏᦻ±²³ஹ´³ᡈ¶©·¸.19.6ᑖ᝞জA5&஺஺Ḅ»CZ
9¼½¾E,$M9(O*$¿ᒹÁ4,5D$,Â-AMÃÂ-ECľ$F.1
᝞ঝÆFᙠECḄÇ>-(aS´ZAMD=ZFMC.2
ÈÉBE=2,CD=1.জS஺0ḄÊ»Ëঝ7ACMÌ9bῪ;:<SAMḄ>ÍÎÏᶇ᪷Ò.20.6ᑖ᝞RtAABC#ZABC=90°,$D,Fᑖ%&AC,ABḄ#$CE/7DB,BE/7DC.1
S´C'

423.8ᑖb᝞+1ᙠ?6ABCDḄ᜜(hADEDCF,AF,BE.+1+2ᜓᵨ+/£ᐵ¥;᝞+2,I"ᩩ“hAOEOCF”¨“ῪhAOEOCF,ªEA=EZ
=«O=FC”,U1
¬Ḅ®¯`ᔲ±ᯠᡂ_³´µᑨ·¸¹º»¼½IhAOEZJC«¾h,ª4C=஺«M஺=«஺,U1
¬Ḅ®¯ÀÁᡂ_ᔩ³´ᑏµÄḄᑨ·.24.10ᑖbᑡ6ÅÆÇᵨ⚪½vᖪÊᵨ8ËᐗÍÎᢇÐÑÒÓÔÕCÖ×├ÙÚᖪÊÛÜញÍÎUWᢇÞßÒÓᦪ`UJḄ2àáÎâãM4ᐗ/®ᐳᵨæ17.6Ëᐗ.çᖪÊUᢇÍÎÒÓèé³ᖪÊ├ÙÞßÒÓ<:^âÀ`58ᐗᒕë150<ᢥíᢚµÙᐰðÙñ.ÙñÞᢇÒÓᖪÊᐳòᑭèéᐗ³25.10ᑖb᝞+᪷ᵯiᩚPQ_ᙠ
ᚁÔøᙢ☢ḄkAùúûᩚ⚔ýkPḄþh45஺ᔣÿ6mᑮB,ᩚ⚔PᩚQḄᑖ60஺30஺ᵯᩚPQḄ.ᶇ᪷!./1426.12ᑖ!"1#$%&'Ḅ(ᱥ""2#ᐸ+,-."AC#/012Ḅ345ᐸ67A8ᙢ☢BDḄAH3.4m.;345AC<9m,=NHAC118஺>?,@AC8ᙢ☢ḄᶇBᦪD$EFGὃᦪIFsin28°=0.47,cos28°=0.88,tan28°=0.53

527.12ᑖzᖪòóôõ9qö*⃩øᕒḄÕ᩽ឋüNýBþ᪗ᳮ᪷᪗ᡂḄ⃩ᕒ〉Ḅᝄ.〉Ḅᨴ├᪗ᖪ!"#$%&'(⃩ᕒᙠ*ᨴḄ├+,ᓫ(./ᐗ1ᦪ᝞4.171816132415282618192217161932301614152615322317151528281619530ᦪᢥ783ᑖ7:᦮ᳮஹ=>?ᑖ᪆᝞4.⚣ᦪᑖB⊤I7DEFGHJ├+134x<1616„x<1919,,x<2222,x<2525„x<282&,x<313L,x<34⚣ᦪ793a2b2ᦪᑖ᪆⊤KᙳᦪMᦪN(ᦪ20.3C18O᪷PQRSTU4ᑡW⚪.YZ.a=—,b=—,c=—[\]ᨴ├+^_`25/ᐗ├᪗ᑣᨵ(⃩ᕒcdᝄ[\efghiḄ⃩ᕒjklᑮ├᪗noᨴ├+pqᔠ〉stuᳮᵫ.wὃUᫀஹ⌱{⚪,|ᜧ⚪ᐳ12⚪'⚪4ᑖᐳ48ᑖ.ᙠ'⚪ḄG⌱⚗Nᨵ⚗ᔠ⚪⌕Ḅ.11ஹB

6ூL᪆௃᪷I"-/:b|a|,IPᑨRᓽ/.ூTL௃Vb|a|,Aa+b<0,|a+b|=-a-b.ᦑ⌱B.ூW௃P⚪Y⌕ὃ[\(ᦪ]ᦪ^Ḅᱯ`aᵨ0cdefḄghi⌕jklm.2ஹDூL᪆௃᪷IopqrᦪḄឋt/uᫀ.ூTL௃2Vy=----Ḅk=-2Vl,"wExyzw▲aVLxAP(a,m)ᙠ}yw▲Vb>L.*.Q(b,n)ᙠ}zw▲,••n1.ᓽm>n,ᦑDFᦑ⌱D.ூW௃⚪ὃ[\opqrᦪḄឋtᑭᵨopqrᦪḄឋtFk"wExyzw▲#L⚪ᐵ.3ஹBூL᪆௃ᐜ⚗"ᫀḄ=ᦪᔠ5=ஹᜧBஹtᙢᙳḄᓱᱏ᪷Iᭆ᳛ᓽ/L.ூTL௃•••ᨵ5=ஹᜧBஹtᙢᙳḄᓱᱏ⚗"ᫀḄᨵᓫ2=

72,¡¢£¤$=£Ḅᓱᱏ☢ា¦#⚗"ᫀḄᭆ᳛#ᦑ⌱B.ூW௃⚪ὃ[\§ᓫ¨©Ḅᭆ᳛.ᵨᑮḄª«Fᭆ᳛=ᡠ®¯ᦪ]°®¯ᦪ±p.4ஹAூ᪆௃ᑖ᪆F²³´ᦪiḄ⊤-4X10"Ḅᐸ14><10,஻᦮ᦪ.¹஻Ḅf>⌕º»¼ᦪ½ᡂ஺>Bᦪ¿7\ÀÁE஻Ḅdef]Bᦪ¿7ḄEᦪ.;¼ᦪdef>1>஻#ᦪÂ;¼ᦪḄdef<1>«#Äᦪ.TL1230000ÅÆᦪᵨ²³´ᦪi/0⊤-1.23x106.ᦑ⌱A.WFὃ[²³´ᦪilmdefᜧx1ḄᦪḄ⊤-Çi#L⚪Ḅᐵ.5ஹDூ᪆௃ᙊ┵ḄÊ☢Ë=Âx807rx90=36007r(cm2).ᦑ⌱D.6ஹBூ᪆௃ÌÍḄdefpÎᜧBdefBḄᨬÐÑ᪗ÓḄÔᳫḄtÖ.ூ௃LF|+5|=5,|-3.5|=3.5,|+0.7|=0.7,|-2.5|=2.5,|-0.6|=0.6,V5>3.5>2.5>0.7>0.6,•••ᨬÐÑ᪗ÓḄÔᳫḄtÖ#-06ᦑ⌱B.ூW௃⚪ὃ[\ᦪÄᦪlmᦪÄᦪḄ¹h0c.h#L⚪Ḅᐵ.7ஹAூ᪆௃ᑖ᪆F×¼ØᑜÚᜩÜ+xÝᑣ(▭ÚᜩÜ+(x+30)Ý᪷IF¼Øᑜᡠᵨ>à-(▭ᡠᵨ>à=2,ᑡÇãᓽ

8/.TLF×¼ØᑜÚᜩÜ+XÝᑣ(▭ÚᜩÜ+(x+30)Ý,10001000᪷I⚪./ᑡÇã:-------------------=2xx+30ᦑ⌱A.WF⚪ὃ[\ᵫ(▭å⚪£wᑖÇãᐵ#æç⚪.ᔠ〉ḄéÖᐵêᑡÇã.8ஹAூL᪆௃᪷Ië¹hᑮᡧḄí<5,ᯠD᪷IᡧḄ☢ËL.ூTL௃]25LFᙊ┵ḄÊ☢Ë=755==.22ᦑ⌱A.ூW௃⚪ὃ[ᙊ┵ḄØïFᙊ┵ḄÊ☢ðñ"$ᡧÅÆᡧḄí<éxᙊ┵☢Ḅᕜ<ᡧḄóôéxᙊ┵Ḅõ<.9ஹDூL᪆௃ᑖ᪆Fö⚪.ªMN=40÷ø/B>x2B>=80÷ø•.•᪷IÇᔣḄ.h@ûḄឋtNM=70஺NN=40஺,᪷Iüᑁ¹ᳮNMPN=70஺./.ZM=ZMPN=70°..•.NP=NM=80÷ø.ᦑ⌱D.10ஹDூL᪆௃•••$ÿᦪy=ax+bḄஹஹ▲/.a<0,b>0,.•.a+bᜧ0,ᦑA┯a-b<0,ᦑB┯,ab<0,ᦑC┯—<0,ᦑD.aᦑ⌱D.11ஹC

9ூ᪆௃⚪!ᦪ"Ḅ#EஹMஹDᐭ%ᑖ'()AOCEஹAOAD,*+OABCḄ☢-.|k|Ḅᐵ0ᑡ)234)k5.ூ௃ᵫ⚪789EஹMஹD:!ᦪ"ᑣSAOCE==SAOAD=>#M?MGJ_y@#G,?MN_Lx@#N,ᑣS°oNMG=|k|.AMB*+ABCOCDEḄF#•'"SABCO=4SONMG=4|k|,L•.•ᦪᙠ▲k>0,.kkc..—+—+9=4k.22I89k=l.ᦑ⌱C.ூ#K௃⚪ὃN!ᦪ0ᦪkḄOP7QRSE"ḄT7#ᑖ'ᔣVᩩᙶ᪗@?ᚖE.ᙶ᪗@[ᡂḄ*+☢-]2|k|,^_#`aὃḄb⌕ὃ#defghiᐵj.12ஹBூ᪆௃•.•ᙠ5.56.5m'Ḅ⚣ᦪ`8,oᦪ`40,,,ᜓ0.Lᦑ⌱B.ஹqr⚪9sᜧ⚪ᐳ6vw⚪xw⚪4ᑖᐳ24ᑖ.z

1013ஹ+■1ᡈ122ூT᪆௃1,ZBWC=90°,᜛AᔠM8cḄNᡠP=+L,2222,NM5'C=90°,NA=90°,AB=AC,ZC=45°,ᡠPRQCMB’ῪFᡠP8M=0+1,ᡠPCM+5M=J55M+5M=J5+1,12ூT௃OᙠᐭT14ஹBE=DFூI᪆௃P¡Ḅᩩ£ᨵBE=DF[¤u.¥G¦ABCDKG¦.\AB=CDZABD=ZCDB>§TBE=DF,AAABE^ACDF(SAS)....AE=CF,ZAEB=ZCFD./.ZAEF=ZCFE..,.AE/7CF5

11...G¦AECFKG¦.(7¦K©ªḄG¦KG¦)ᦑUᫀBE=DF.215ஹ5ூ᪆௃()C,D,E,F,G|v#aT7}#mᡂ2ῪD+Ḅvᦪ᪷ᭆ᳛3ᓽ8).ூ௃•.•C,D,E,F,G|v#aT7}#ᐳᨵ5ᐸaAஹBஹCAஹ5ஹV}mᡂ2ῪD+2ᡠD+2ῪD+Ḅᭆ᳛`2ᦑᫀ`9ூ#K௃ὃNḄ`ᭆ᳛3AḄᭆ᳛(A)=A)Ḅᦪ.ᡠᨵ)ḄᦪḄᖪ`I¢⚪Ḅᐵ£.16ஹ24aூ᪆௃᪷⚪7ᑡ)¤ᦪ3ᓽ.ூ௃᪷⚪78930ax0.8=24a,ᑣg¥ἠ§o¨B24aᐗᦑᫀB24a.ூ#K௃ὃNªᑡ¤ᦪ3«¬⚪7`I⚪Ḅᐵ£.17ஹb1+1)2ூ᪆௃⚪ὃN®3ᑖIḄQ✌ᐜ±²}vᐳ⚗b,ᡠ±a2b+2ab+b=b(a2+2a+l)ᵫ´ᐰ¶·3(X1+X2)2=X12+X22+2X1X2ᡠ±a2b+2ab+b=b(a2+2a+l)=b(a+1)21018^—7ூ᪆௃

12᪷⚪NḄ®ᓄ°ᡠ±²±²ḄTᓽ.ூ௃᪷⚪´d.l-lx2=^xl-l,xX343475—x=—,126Td.x=—,ᦑUᫀx=—.ூµ௃⚪Ḅᐵ·¸¹º»¼ᑣ½ᓄᡂᐗᐗ¾±²¿T5ᐗ¾±²ᓽ.FஹTU⚪.(|ᜧ⚪ᐳ9⚪ᐳ78ᑖTUÀᑏᦻÃtuஹ¤uIJᡈÅ»ÆÇ.19ஹ(1)ÈT᪆[(2)2ঝ1ᡈ+ioூ᪆௃(1)eÉʤuNAMD=NADC,NFMC=NADCᓽTËW⚪[(2)জᙠRtAOCENᑭᵨÏÐᳮ᪀Ò±²ᓽTËW⚪[ঝᑖÔÕÖ×Tᓽ.ூ௃T.(1)¤u.᝞ঝNØÙACஹAD.ঝ"ABA.CD,.CE=ED,.AC=AD,.ZACD=ZADC,VZAMD=ZACD,.ZAMD=ZADC,VZFMC+ZAMC=110°,ZAMC+ZADC=110°,.ZFMC=ZADC,

13.ZFMC=ZADC,:
NFMC=NAMD.(2)I9জ᝞ঝ-1a»¼0C.½஺஺Ḅ¿ÀBr.3ঝᙠRtAOCEaVOC2=OE2+EC2,:.=(r-2)2+42,.r=2.ঝ,:NFMC=NACD>NF,•,•ÁᨵV+9MF=FC,FM=MC.᝞ঞaÃ᧕ÅÆCM஻AO,AM=CD.AM=CD=1.᝞টaÃMC=M/»¼M஺ÉÊM0F4஺ট■:ZMFC=NMCF=ZMAD,NFMC=ZAMD,.Z.ADM=ZMAD,

14:.MA=MD9•*,AM=MD
:.MHVADAH=DH99ᙠRtAAEQa4஺=%+8?=46,
.AH=2,
.OH=y[5,:.MH=2+,ᙠRtAAMHaAM=J(2Ì)+(5+⌲=750+10Ì.ூ#K௃⚪ὃNªᙊḄÑᔠ⚪9ÓÔÕ.ᙊᨵᐵḄឋ×ஹᙊḄᑁ¼·+Ḅឋ×ÙÚÛḄឋ×ÜᮣÞᑭᵨᐰ2D+Ḅឋ×Üáᑭᵨ☢-ḄÙâãäåᑣOP+Ḅ☢-.20ஹ(1)æI᪆;(1)4⊈ூI᪆௃(1)᪷¶éê+Ḅᑨᳮ✌ᐜí^ê+O8ECB¶éê+ᯠïᵫðDD+ñê"ḄaE2ñêḄ¿8ᑮᐸóêô29CD=BD,8ÅÜ(1)ᵫD+a:EᳮÙõöᳮ48A5êḄÊiᯠï᪷÷+Ḅឋ×ÙD+Ḅ☢-3øéI.ூùI௃(1)ÅÆ9VCE/7DB,BE஻DC,ê+DBECB¶éê+.AYRtAABCaZABC=90°,#D`ACḄa#.*.CD=BD=-AC,2¶éê+DBEC`÷+Ü(1),••#D,Fᑖ'`AC,ABḄa#AD=3,DF=1,.••DF`AABCḄa:EAC=1AD=6,SBCI)=-SABCAA2.,.BC=1DF=1.ANABC=90஺,

15/.AB=7AC2-BC2=.•KG¦DBECÚ.11r-r-••StsuiKDBEC=1SABCD=SAABC=-AB*BC=—x4,2xl=4,2•µ.|⚪ὃÛÚḄᑨឋÞFߦQḄNà`ߦḄgFN(àᳮ.ᵫ஺ACḄNdᑮ0=5஺TU1
Ḅᐵ·ᵫÚḄឋÞ?FḄ☢ãäådᑮSGæOBEC=SAABCTDḄᐵ·.21ஹ1
'ᨴçèᡂ|Ḅ4é᳛5%2
⚜ì4ᨴíîäïḄçèᡂ|342.95/ᐗ.ூ᪆௃1ð'ᨴçèᡂ|Ḅ4é᳛x,᪷2ᨴíஹ3ᨴíḄçèᡂ|ᓽdᐵ`xḄᐗE¾±²Tñòᐸôõᓽdö×[2
ᵫ4ᨴíîäïḄçèᡂ|=3ᨴíîäïḄçèᡂ|x1-4é᳛

ᓽdö×.ூ௃1ð'ᨴçèᡂ|Ḅ4é᳛x,᪷⚪´d.4001-x
2=361,Td:xi=0.05=5%,X2=1.95,^ᔠ⚪´øù1.U.'ᨴçèᡂ|Ḅ4é᳛5%2
361x1-5%
=342.95,/ᐗ1:⚜ì4ᨴíîäïḄçèᡂ|342.95/ᐗ.ூ௃|⚪ὃÛᐗE¾±²ḄÀᵨT⚪Ḅᐵ·.1
úûüᐵýþᑡᐗE¾±²[2
᪷ᦪüᐵýᑡå&».22ஹÈT᪆ூ᪆௃ÿ⚪ᑖ᪆ᓫḄᡠᙠḄᐰᔠ⚪ADB^^AEBᓽ.⚪᪆AB=AC,DBCḄAD_LBC,.\ZADB=90°.VAE±EB,.\ZE=ZADB=90°.TAB!ᑖNDAE,
NBAD=NBAE.

16ᙠ4ADB"^AEB,NE=NADB,NBAD=NBAE,AB=AB,.,.ADB^AAEB(AAS),/.AD=AE.23ஹ(1)AF=BE,AF1BE(2)&᪆'(3)()ᯠᡂ,ூ᪆௃⚪ᑖ᪆(1)᪷./0"1ABEgZiDAF,ᯠ23BE=AF,NABE=/DAF,456783BE±AF(2)9:(1)Ḅ;AABEgZXDAF,ᯠ23AF=BE,AFJ_BE,<=(>ᡂ,'(3)9:(1)(2);ᐜAAEDgDFC,ᯠ2@AABEAADAF,<=3(.⚪᪆(1)AF=BE,AF±BE.(2)(ᡂ,.B1ABCD/0/.BA="AD"=DC,ZBAD=ZADC=90°.ᙠAEAD"AFDC,EA=FD,{ED^FC,AD=DC,.,.EAD^AFDC..•.ZEAD=ZFDC.CZEAD+ZDAB=ZFDC+ZCDA,BPZBAE=ZADF.ᙠ^BAE"AADFBA=AD,{NBAE=NADF,AE=DF,/.BAE^AADF.
BE=AF,ZABE=ZDAF.VZDAF+ZBAF=90°,

17/.ZABE+ZBAF=90°,/.AF±BE.3
úᡂû.ὃ#9·+2êD+D+ᐰ224ஹ(1)2000:(2)90260ᐗ.ூI᪆௃1
½ᖪýᢇÿ
xᑣᢇ
2x᪷ᓫ=+ᦪᔠᢇᢇḄ4ᐗ/ᓽᐵ!xḄᑖ#$%&'()*+ᓽ,-2
ᵨ1
Ḅ,x2/ᢇ01
Ḅᦪ2ᑭᵨᑭ4=├6ᦈᐭ-ᡂ;ᓽ,.ூ>&௃&@1
A0ᖪCᢇ
xᑣᢇ
2x17600080000᪷⚪E:=4,2xx&@x=2000,()*x=20
0Gᡠᑡᑖ#$%Ḅ&JKᔠ⚪E.L@ᖪCᢇ
2000.2
2000x2=4000MN2000+4000-150
x58+150x58x0.8-80000-176000=90260MᐗN.:6OPQᢇ
ᖪCᐳSᑭ90260ᐗ.ூTU௃;⚪ὃWᑖ#$%ḄXᵨ&⚪ḄᐵYG@1
Z[\ᐵ]^_ᑡᑖ#$%-2
᪷ᦪᐵ]ᑡ#`a.25ஹ(6+273)cூ&᪆௃᪷efḄghiACQ=x,BC=GQC=#X,PC=&BC=3X,᪷PQ=BQᑡ$%/&ᓽ.ூ>&௃&@jkPQlᙢ☢oTC,

184ᵫ⚪E@AB=6m,ZPCA=90°,NPAC=45஺ZPBC=60°,NQBC=30஺ACQ=x,ᑣᙠRtABQCtBC=GQC=&X,.•.ᙠRtAPBCtPC=V5BC=3X,•ᙠRtAPACtNPAC=45°,vIwPC=AC,A,3x=6+6x,&x=3=3+x,•
.PQ=PCCQ=3x-x=2x=6+2zᑣᵯ|ᩚPQ~6+2+Nc.ூTU௃⚪Tὃ&iiḄᳮ&&iiḄ$G&⚪ḄᐵY.26ஹCᙢ☢Ḅ~7.6m.ூ&᪆௃ᑖ᪆@CEJ_BD!F,AF_LCE!F,᝞2,᧕gAHEFᑣEF=AH=3.4m,ZHAF=90°,2`aNCAF=28஺ᑣᙠRtAACFtᑭᵨ^`aCF,ᯠ+`aCF+EFᓽ.>&@CELBD!F,AFLCE!F,᝞2,2᧕gAHEF/.EF=AH=3.4m,ZHAF=90°,ZCAF=ZCAH-ZHAF=1180-90o=28°,ᙠRtAACFtVsinZCAF=-AC.CF=9sin28°=9x0.47=4.23,.•.CE=CF+EF=4.23+3.4*7.6m
,L@Cᙢ☢Ḅ~7.6m.TU@;⚪ὃW&iiḄXᵨ@ᐜ▭⚪ᦪ⚪M¡☢᪀⌼ii¤ᓄ&ii⚪Nᯠ+ᑭᵨ¦§¨ᳮhi©ᦪḄ¨ª«¬`a.

1927ஹ(1)DᦪF15(2)3,4,158(3)ᨴ├IJKF18LᨵNOPQḄ⃩SᕒUVᑮ├IX᪗.ூ᪆௃᪷.ᦪ.3ᑮZᙠ[B\ஹ[]\Ḅ^ᦪᑖ_F3^ஹ4^ᡠ`a=3,b=4,@᪷.ᦪ.315abc5dabdᦪᨬfᡠ`Dᦪc=15g⚣ᦪᑖi⊤`kaᨴ├IJlmn25LᐗḄ⃩Sᕒᨵ8^ᡠ`p⚪qᫀF8⚪ὃtuᦪḄvw᪷.uᦪ`xNOPQḄ⃩SᕒVᑮ├IX᪗.ூ௃(1)ᙠ22,x<25zᑁḄᦪ.ᨵ3^ᙠ2&,x<31zᑁḄᦪ.ᨵ4^15abḄdᦪᨬᜧᑣDᦪF15(2)ᨴ├IJlmn25LᐗF2☢\ᦪ.ᓽᨵ8u⃩Sᕒ3ᝄ'ᦑqᫀF3,4,158(3)xNOPQḄ⃩SᕒUVᑮ├IX᪗ᡃFᨴ├IJKF18Lᔠ〉.