2021年河南省中考数学仿真试卷（一）（附答案详解）

《2021年河南省中考数学仿真试卷（一）（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
ᓭḕὃᦪᔁஹ⌱⚪ᜧ⚪ᐳ10⚪ᐳ30.0ᑖ1.2021Ḅ᎔ᦪA.2021B.-2021C.≶D.2.᝞()*+Ḅ,-(ᑣ/“ῃ”3ᡠᙠ☢78Ḅ☢9᪗Ḅ;3A.D.ᑭ3.ᰚBCDEFGḄ“HI”FGJḄKLMNKLOPQRSPTU.VWXYᵨ᜜\FGḄᰚBC]^_`0.000156cd0.000156ᵨ\eᦪf⊤hi`A.0.156xIO-3B.1.56x10-31.56x10-4D.15.6x10-4c4.oᑡqr)sḄA.a2+a2=a4B.a23=a5C.a+2=2aD.a/?3=a3b35.xyyz{/ᙽ}~᝞(W=zl=48஺ߟ7^ᑣ42Ḅ^ᦪ`\Q/A.38°1\//B.42°C.48°D.52°6.ᙠᚗᑖ᪥ஹᔜᨵ100ᵱᡂ£Ḅ¤¥᳛`40%,᝕ᡂ£Ḅ¤¥᳛`60%,ᵱᡂ£Ḅ¤¥᳛`50%,᝕ᡂ£Ḅ¤¥᳛`70%.8ª«Ḅᡂ£o☢ᨵ}¬®¯জᵱᡂ£Ḅ¤¥᳛ªᵱᡂ£Ḅ¤¥᳛±ঝᡂ£Ḅ¤¥᳛³ªᡂ£Ḅ¤¥᳛±ঞஹᡠᨵᵱᡂ£Ḅ¤¥᳛³ªஹᡠᨵ᝕ᡂ£Ḅ¤¥᳛.ᡠᨵᔠᳮ®Ḅ·¸A.জঝB.জঞC.ঝঞD.জঝঞ

17.¹ºᔆ¼ᜓ¾400ᝅÀÁºᙠ¾Â160ᝅÃÄᵨÅÆᢈÈÉ=¾Êᦔ᳛ÌÍqᑜÏÐÅ20%,ÑÒᐳᵨÅ18ᜩÂᡂÔÕÖqᑜ×ᜩ¾¹ºØÙᝅÚᙠÛ¬Ö⚪Üqᑜ×ᜩ¾xᝅ¹ºᑣ᪷Þ⚪ßà=*á`A160.400-160400A,1(1+20%)%=18B.â+(1+20%)¾=18400-160yc400400-160=18c.—X+--20%--x=lox(1+20%)¾8.᝞(ᡠhäåᦪy=ax2+bx+caR0(èḄéᑖêëoᑡìfí)sḄA.ac<0B.a—b+c=0C.î2,y1ï2,ðᙠñᱥó9ᑣyiõö2D.ñᱥóḄ8Eø`zóx=19.᝞(ᙠùúûA8CQ,AD஻BC,4஺=90஺,4஺=4,BC=3.ᑖýþîA,C`ᙊ
ᜧ,E,BEAZAC0.஺ACḄ
ᑣCCḄA.2V2B.4C.3D.V1010.᝞$
ᙠ&☢()ᙶ᪗,,-./ABCDḄ⚔ᙶ᪗ᑖ341,-1,8-1,71,C78…:;“-./Ḅ=>”
ᐸA1
ᵨC
DC,E
…ḄᙊGHB,C,D,AIJ
ᑣ42021Ḅᙶ᪗K2⚓
ᐳ25⚓

2A.(-4043,-1)D.(-4041,-1)NஹPQ⚪Sᜧ⚪ᐳ5T⚪
ᐳ15.0ᑖ11.ᵨUᦪW⊤YZᦪaa>0
Ḅ&.᪷\.12.7ᐗNH.^/+4x+c=0ᨵbcdeḄZᦪ᪷
ᑣcḄfghᑏj7bᓽg.13.“lᓣᦪ”7bᦪnoᦪpqroᦪpᜧḄsᯠᦪ᝞\34,568,2469e.uv7bwᦪ
“lᓣᦪ”Ḅᭆ᳛.14.z/ABC஺Ḅᕜ8,|)AC,dO,EABḄ
ᑣOEḄ.15.᝞$
ᙠ-./ABC஺᜜~(AP,Bᐵ(4PḄ|E,8E,DE,ᐸ(஺E(4F,4DE=25°,ᑣNF4B=.ஹ⚪Sᜧ⚪ᐳ8T⚪
ᐳ75.0ᑖ16.jbᑖW\3,bᑖWHsPᐭᑡl
______+______+,ᓄ
j=71Ḅf.

317.201911ᨴ
Ẇ¡▾£¤¥¦§ᩗ©ª«¬&®᫆
ὶᔠ²³4P´µ4/¶·ᐗ-2019¸¹º»¼§½¥¦§ᩗ²¾¿ÀÁÂ,¿ÀÁóÄ2019¸¹º»¼Å½¥¦§ᩗÆÇÈÉÊË
|500Ì͸¹º»¼ÎÏŽÐÑÒÓÔÕᑖ100ᑖ
Ö×ᑖ3\ØஹÙÚஹÉÛ.|ÜᑖᵫÞᑮàḄÖ41ÍŽḄᨵᐵᦪáÐÑᦈãஹ᦮ᳮஹæçèᑖ᪆.☢jÄêᑖëì\a.ÜᑖḄ⚣ᦪᑖ³(.$\c.41ÍŽîïᡠᙠñòᑖ³$có᦮᝞$\ôõöᶇ7wTᦪ北京3.深圳5377%家上海m家杭州2家广州2家苏州1家合肥1家南京1家d.øùªᢈûüᨵ▲ÃþḄ¥¦§ᩗÆÇÈÜᑖ70.3.hlᦪáᩭ
PA/ᐗ-2019ᩗ᪷!ᑡ#⚪%1
&'(ᢈ*+ᨵ▲./Ḅᩗ1234ᑖ᣸789;2
;<ᙠ⚞?@4ABᡂDEᐸᙠGHஹJKLMNOP
QḄR⚞?;

4?w4
!ᑡxyᔠᳮḄ8.}~জW41GQḄᩗ1234ᑖḄᦪᙠ65<%<70ᦪᙠ65<%<70ḄឋᨬᜧwঝW41GQᑖY
ᡃ8gh.Ḅ
ஹ(ᢈஹᦟḄghghᓅḄEᐸo¡aᓫ£¤ḄQᐙᑖ¦§ᓅᙠ⚞?Ḅ¨.18.᪷⍝ª«¬®®¯%°¬᫑᫡³▲´40km".µ¶·ᐰ«¬¹ºᙠ᫑ᜮ¼½¾¿À%“[Âô”ÅÆÇ᤬ÉÊËÆÌ᝞iᙠÎÏ.ªLª᫑Ð8cᑁ▲´40km",µ¶ÒÇÓÔ8ᔲôᙠÖ×.ªL500ØÙḄAᜐÛ½¶ÜÇÝÞÜÇÝAÇ4ßÓÞÝ8ᑮÝCVM¶30áâTã4BL=45஺^ACL=30°,åÓô¶ᔩç[èéᳮᵫ.}ëὃᦪ%í=1.41,V3=1.73

519.᝞iᙠð☢Ïòᙶ᪗ÊxOyÏ/%y=x-1ḄiùNúûüýᦪy=^(x>0)Ḅ4(3,m).(1)ZḄ(2)PQp,0)xḄ!xḄᚖ#$#/M,'()*ᦪy=2>0)ḄN..ஹ0ᙶ᪗3᦮ᦪḄ56᦮7y=(%>0)ḄᙠA,N<=Ḅ>ᑖ@#AAM,MNBᡂḄDE(FGHI)JW.জMN=5PDEWᑁḄ᦮Ḅᙶ᪗JঝSDETᑁាᨵ6X᦮Yᔠ*ᦪ[\Ḅ]B.20.᝞AABCbAB=AC,cACJ$dḄ஺஺8C஺ABE,JAChi#jBAC=2CDF.(1)klOF஺஺Ḅᑗ#(2)pqOE,klDE=DB(3)ScosB=1,CF=2,஺0Ḅud.v6⚓ᐳ25⚓

621.ᙠᢙz{|}~ᡊᧅbᨵ152ᐳ■ᵨ⌕ᑮ4ஹ8╋Sᵨᜧᐳ15ᑣាឋᢇ■ᵨᜧḄ¡ᑖ¢J12/£8/ᐸbᵨᜧ¥AஹB╋Ḅ¦ᑖ¢J§800ᐗ£900ᐗᵨ¥AஹB╋Ḅ¦ᑖ¢J§400ᐗ£600ᐗ.(1)15bᜧᔜª«¬(2)®᣸ᐸb10°¥A╋ᐸ±°¥B╋²°¥A╋ḄᜧJx°¥Aஹ8╋³¦ᵨJyᐗ´[y@xḄ*ᦪµ᪆·.S¥A╋Ḅ■ᵨF«100¸¹ᑏ[»ᔠ⌕Ḅᨬ«¦ᵨ.22.᝞ᙠ½¡BCbAB=6cm,PABḄ¾஺BChi#Ḅ¿pqOPACQ.À᪷ÂÃÄÅᦪḄÆÇ.È#AAP,DP,QQḄiÉ<=ḄᐵËÌÍÎÏÐ.Ñ☢ÀḄÏÐÓ¸⊡ᐙ᦮l(1)ÈPᙠABḄFÖ×ØÙஹÚÛÜᑮÎ#AAP,DP,஺஺ḄiÉ(ᓫ×lcm)ḄÞß᝞⊤l

7×Ø1×Ø2×Ø3×Ø4×Ø5×Ø6×Ø7AP0.001.002.003.004.005.006.00DP4.994.564.334.324.534.955.51DQ4.993.953.312.952.802.792.86ᙠAP,DP,OQḄiÉáXÛbâ¿ḄiÉãäÛḄiÉ£ḄiÉ3XãäÛḄ*ᦪ;(2)ᙠÖæ☢$çᙶ᪗ËbÙ[(1)bᡠâ¿Ḅ*ᦪḄ;(3)Yᔠ*ᦪµéê⚪lMAP=^T/^+^^îïAPḄiÉðJ,v8⚓ᐳ25⚓

823.ூ▅óᩞᧇ௃পÀ⍗ᑮ᪵Xê⚪l᝞1,PᙠúHáçûABCᑁj஻PC=150஺PA=6,PC=8.P8Ḅi.Àý,þaPACÿA
┐ᔣ60஺ᑮ4DB,DP,ᵫឋABD,PC=BDᵫN4PC=150஺NPDBḄᜧPBḄ.!"#ᙠ%1&PDB=°,PB=.ூ(⚪*+௃(2)-ὃ/0ὃ(⚪Ḅ1*+2☢(⚪#᝞%2,AABC&54cB=90஺sin^ABC=y.Pᙠ4BCᑁ7PA=2,PB=2A/10,PC=3&.ABḄ.ூᮣ9:ᵨ௃(3)᝞%3,ᙠ4BC&tan/B4c=1,AD1BC<஺=B஺=6,CD=4.ABCḄ☢?.

9"ᫀA*᪆1.ூ"ᫀ௃Dூ*᪆௃*#-2021Ḅ᎔ᦪE-⊤.ᦑ⌱#D.᪷KL?E1ḄMNᦪOP᎔ᦪᑨRᓽ.T⚪U⌕ὃWX᎔ᦪYZ[\]ᐵ_`E*⚪ᐵa.2.ூ"ᫀ௃Cூ*᪆௃*#YbḄ⊤☢cd%]eḄ☢fgh_]◞hNYj“ῃ”n“o”E]e☢.ᦑ⌱#C.YbḄ⊤☢cd%]eḄ☢fgh_]◞hNYj᪷Kphᱯr".s⚪U⌕ὃWXYb]eMN☢tḄᦻvwxYbḄyg%jz]e☢ᐭ|,ᑖ᪆*"(⚪.3.ூ"ᫀ௃Cூ*᪆௃*#0.000156=1.56x10-4.ᦑ⌱#C.e<1ḄYᦪᑭᵨᦪ1⊤hjPax10-«,nᜧᦪḄᦪ1ḄEᐸᡠᵨḄE᦮ᦪᢣᦪᢣᦪᵫᦪhNPḄᦪv☢Ḅ0ḄNᦪᡠ+_.s⚪ὃWᵨᦪ1⊤ḄᦪhjPax10",ᐸ&1<|a|<10,஻PᵫᦪhNPḄᦪv☢Ḅ0ḄNᦪᡠ+_.4.ூ"ᫀ௃Dூ*᪆௃*#A.a2+a2=2a2,ᦑA⌱⚗┯;8.(Q2)3=Q6,ᦑ8⌱⚗┯¢10⚓ᐳ25⚓

10C.a+2¥1¦§ᦑC⌱⚗┯¢D.(ab)3=a3b3,ᦑ஺⌱⚗YZ.ᦑ⌱#D.ᑖ¨ᑭᵨ©ḄL:§1ᑣᔠ¬⚗1ᑣA?ḄL:§1ᑣᓄ¯°"ᫀ¢s⚪U⌕ὃWX±ḄL:§ᔠ¬⚗A?ḄL:§²³YZ´ᵨ:§1ᑣE*⚪ᐵa.5.ூ"ᫀ௃Bூ*᪆௃*#••"1=48஺,•••Z.3=90°-Z1=90°-48°=42°.•••¶·ḄMO]¸¹•••Z2=Z3=42°.ᦑ⌱#B.ᐜ᪷K»¼Ḅ_`°43Ḅ½ᦪ¾ᵫ¸¹¿Ḅឋᓽ°ÀÁ.s⚪ὃWḄE¸¹¿ḄឋᵨᑮḄ³P#M¶¿¸¹¼]².6.ூ"ᫀ௃Bூ*᪆௃*#•.ÃÄÅᵱÇᡂÉḄÊË᳛P40%,ÍÄÅᵱÇᡂÉḄÊË᳛P50%,ÎÃÄÅᵱÇᡂÉḄÊË᳛<ÍÄÅᵱÇᡂÉḄÊË᳛¢ᦑজYZ•••ÃÄÅÇᡂÉḄÊË᳛ᙠ40%n60%fgÍÄÅÇᡂÉḄÊË᳛ᙠᙠ50%n70%fgÐZ_ÑNÄÅḄÊË᳛ᜧᦑঝ┯¢••ÃஹÍÄÅᡠᨵᵱÇᡂÉḄÊË᳛ᙠ40%n50%fgÃஹÍÄÅᡠᨵ᝕ÇᡂÉḄÊË᳛ᙠ60%n70%fg.ÃஹÍÄÅᡠᨵᵱÇᡂÉḄÊË᳛h_<ÃஹÍÄÅᡠᨵ᝕ÇᡂÉḄÊË᳛.ᦑঞYZ.ᦑ⌱#B.

11᪷K×°ᩩÙᑭᵨÚ¦³⌲hÜᑨR.s⚪ὃWÚ¦³Ý<&᫏⚪.7.ூ"ᫀ௃Aூ*᪆௃ூᑖ᪆௃s⚪ὃWXᵫá▭(⚪ãä°ᑖåæ°⚪ç&Ḅᐵaèæᑮ]´Ḅ²éᐵêE*+(⚪Ḅᐵa.wxërg=ërìé+ërᦔ᳛.ᐵaïðèP#“ᐳᵨX18ᜩôᡂõö”,÷ø²éᐵêP#ùᵨúᢈüᡠᵨg+ùᵨúᢈüýᡠᵨg=18ᜩ.ூ*"௃*#þ¦ᑜᜩxᝅᵨᢈᡠᵨᵨᢈᡠᵨ400-160:(1+20%)/flLLᓝITL7160400—160ᑣᡠᑡT+6⁰᪹$=18.ᦑ⌱A.8.ூ-ᫀ௃Dூ0᪆௃0ᵫ3456a>0,Z?<0,c<0,••.ac<0,ᦑ⌱⚗AAB$CD=—1y=a—b+c=0,ᦑ⌱⚗BAB$I(K2/1)O(2/2)ᙠQᱥSTᑣU1>ஹ2,ᦑ⌱⚗CAB$QᱥSḄYZ[\SD=]T=aᦑ⌱⚗஺_AB$ᦑ⌱D.᪷abᦪ34OdebᦪḄឋg5hᑨjᔜl⌱⚗mḄnopᔲABrs5h0-t⚪.t⚪ὃwdebᦪ34TIḄᙶ᪗ᱯIஹdebᦪḄឋg0-t⚪Ḅᐵ|p}B⚪~,12⚓ᐳ25⚓

12ᑭᵨᦪᔠḄ0-.9.ூ-ᫀ௃Aூ0᪆௃ூᑖ᪆௃t⚪ὃw3-t3ᳮSᚖ\ᑖSḄᑨឋgᐰ]Ḅᑨឋg〉m.CF஺p0⚪Ḅᐵ|.C,᪷at3560Eᚖ\ᑖAC,ᵫᚖ\ᑖSḄឋg6¡F=FC,¢᪷aASA£}¤FOA^LBOC,¡F=BC=3,¥¦ᣚ6ᑮFC=AF=3,ᑭᵨSḄO©ᐵª«஺=AD-AF=1.ᯠᙠ\¤FDCmᑭᵨᳮCDḄ.ூ0-௃0᝞3C,ᑣ4F=FC.„/£/VAD஻BC,Z.FAO=Z.BCO.ᙠ4?஺?!ABOCm/.FAO=Z.BCO0A=0C,LAOF=COB.-.^FOA^/s.BOC(ASA'),AF=BC=3,FC=AF=3,FD=AD-AF=4-3=1.ᙠ4FOCm•••Z.D=90°,CD2+DF2=FC2,•••CD2+l2=32,•••CD=2\/2.ᦑ⌱A.10.ூ-ᫀ௃Bூ0᪆௃0r3m5h°4Ḅᙶ᪗p±ߟ1,K3,³Ḅᙶ᪗p±K51´Ḅᙶ᪗p
L7´Ḅᙶ᪗p
9,K1

132021+4=505...1,dI/021Ḅᙶ᪗p&Ḅᙶ᪗·¸ḄI.¹e·¸ᑣ42஺21Ḅºᙶ᪗p-1»ᙶ᪗K(1+2x2021)=-4043.½2021Ḅᙶ᪗p(ߟ1—4043).ᦑ⌱B.ᐜᑖ¿4Ḅᙶ᪗p(K1,K3),ÀḄᙶ᪗p%Ḅᙶ᪗p(1,7)4Ḅᙶ᪗p(9,-1),rmÄÅƹÅÆÇÈᓽ5.t⚪ὃw\ᙶ᪗ªᑁIḄᙶ᪗ËÌÍᓄÅÆ0⚪Ḅᐵ|pᳮ0AIḄᙶ᪗◀ÐᔠÍᓄÑ᜜ÓᵫÔÕÖ×BsØÔÕKeÖ×Ù2.11.(-ᫀÚ+Voூ0᪆௃0ᵨ¦ᦪÝ⊤ßàᦪa(a>0)Ḅá᪷âãᦑ-ᫀä஽.᪷aæáËÈ56KlᦪḄá᪷.t⚪ὃwá᪷ᐵ|p᪷aá᪷Ḅç0-.12.ூ-ᫀ௃1(-ᫀ_èK)ூ0᪆௃0••Kᐗdeá/+4x+c=0ᨵël_ìḄàᦪ᪷•••¤=16—4c>0,06c<4,ᦑcḄí5hp1.ᦑ-ᫀ1.(-ᫀ_èK)\ᑭᵨ᪷Ḅᑨ¿Ý6¤>(),îsCḄðᑏKlÐᔠ⚪~Ḅᓽ5.ò⚪ó⌕ὃw᪷Ḅᑨ¿ÝAB6¤ḄÐõp0⚪ᐵ|.Kᐗdeáa/+bx+஺=09K0)Ḅ᪷4=᮱K4ỏᨵ᝞ùᐵªজCA>0áᨵël_ìḄàᦪ᪷$ঝC¤=()áᨵëlìḄàᦪ᪷$ঞC¤<()áýàᦪ᪷.13.ூ-ᫀ௃0.414⚓ᐳ25⚓

14ூ0᪆௃0ëþᦪKᐳᨵ99—10+1=90l,Tᓣᦪ
12,13,14,15,16,17,18,19,23,24,25,26,27,28,29,34,35,36,37,38,39,45,46,47,48,49,56,57,58,59,67,68,69,78,79,89,ᐳ8+7+6+5+4+3+2+1=36.ᭆ᳛
36+90=0.4.ᦑᫀ
0.4.ᐜᑡᡠᨵᓣᦪ᪷ᭆ᳛ᓽ.᝞!ᨵ஻#$%&'(!Ḅ$ឋ+,ᐸ.!A/0#1,34!AḄᭆ᳛P(4)=᧕┯789ᑮᓣ;<ᦪḄᦪ.14.ூᫀ௃1ூ᪆௃•.•ABCA3CQ8DC,AC1BD,•••E8A8Ḅ.7OE=-AB,2•DCABC஺ᕜG
8,•AB=2,1•OE=-x2=1,2ᦑᫀ
1.᪷DCឋHIAB,᪷JKLKCMBḄ.NOPMBḄQᓽI9OE.R⚪T⌕ὃWDCḄឋHXJKLKCMBḄ.NḄឋH⚪ḄᐵZ8[\]^JKLKCMBḄ.NOPMBḄQ.

1515.ூᫀ௃20஺ᡈ110஺ூ᪆௃ூᑖ᪆௃a⚪T⌕ὃWḄ8bcCḄឋHஹOῪLKCḄឋHஹfᢚḄឋHh⚪ijkᔠ⚪iḄmC8⚪ḄᐵZ.✌ᐜh⚪ijmCᯠpqrA4EB
OῪLKCᯠphLKCḄᑁKXtᳮIᓽ.ூ௃᝞vmᡠwxyAE.•••7Bz7EᐵP4P{|,•••AE=AB,Z.EAF=Z.BAF.•■AE=AD.•/.ADE=25°,Z.EAD=130°,•••AEAB=130°-90°=40°.1/-BAF=-AEAB=20°,2᝞vmᡠwxy•78z7EᐵPAP{|,AAE=AB,/LEAP=Z-BAP.}16⚓ᐳ25⚓

16•AE=AD.v/LADE=25°,:.LEAD=130°,Z.EAB=360°-130°-90°=140°APAB=^AEAB=70°,.4BAF=180°-/.PAB=180°-70°=110°.ᡠ4BAF
20஺ᡈ110஺.ᦑᫀ
20஺ᡈ110஺.11x*2-x16.ூᫀ௃x+1x-1X2-2X+1ூ᪆௃ᫀ᝞++x-1+x+l஺-1)2=Q+l)(x-l)x(x-l)2xX-1(x+1)(x-1)X2~~,x+1X=1,==V2.1x2-xᦑᫀ
x-1,X2-2X+1"᪷ᑖḄ0ᑣᑖḄ◀ᑣᓄᯠpXḄᐭᓽIᫀ.a⚪ὃWᑖḄᓄI⚪ḄᐵZ8[\ᵨᑖḄ0ᑣ◀ᑣa⚪¡P¢Ạ⚪¤.17.ூᫀ௃16945জঝூ᪆௃(1)¨©ªᢈ¬ᨵ▲¯Ḅ°±²ᩗ´µ¶9ᑖ᣸¸8}16¸¹(2)º»¼½ᙠa¿᣸À.Ḅ9ᑖᜧᭆ894ᑖ¹ব•••41ÃÄÅÆᙠᙠᓅÈḄᨵ41x53.7%«22Õ••ᙠ41ÃÄÅÆᡠᙠÉÊᑖËm.m=41-7-22-2-2-1-1-1=5᝞vm.▢ÍÎᑖ᪗⊤ÑḄÒÓ

17北京3.深圳5377r家上海m家杭州2家广州2家苏州1家合肥1家南京1家(4)Ö×ᔠᳮḄ8জঝᦑᫀ
(1)16¹(2)94¹(3)5¹(4)জঝ.஺)᪷ᩩCß»m.Ḅàáᓽ9ᑮ1â¹(2)᪷ᩩCß»m.Ḅàáᓽ9ᑮ1â¹(3)᪷ᡧCß»m.Ḅàáᑡ»ᓽ¹(4)᪷ß»m.Ḅàáᑨ×ᓽ.a⚪ὃWå$ឋḄᜧæᩩCß»m¹ᡧCß»mbçᳮ⚪i8⚪ḄᐵZ.18.ூᫀ௃Réêëì.ᳮᵫ᝞vîAð40J.BC,ᚖö
஺÷ø஺=500,•••4ABL=45°,/.ADB=90°,500•tan45°=——BD,.BD=500.ACL=30°,/.CAD=60°8C+500•tan60°=————500=50073-500«366.éì
ü=12.2m/s.•••40km/h=zall.l(zn/s),•••12.2>11,1,;.ூ᪆௃᪷⚪ᔠ┦ᦪᐵ"#$BQ,BCḄ)*+,-$.Ḅ/*+,#$0ᫀ.218⚓*ᐳ25⚓

18⚪5⌕ὃ89:;<ᳮ>?┦ᦪᐵ"Ḅ@ᵨ*#$8cḄ)B⚪ᐵC.19.ூ0ᫀ௃(4,2)ூ᪆௃E(1)FG4(3,m)Hᐭy=x-1#m=3-1=2,•••GJᙶ᪗M(3,2),••G4ᙠOPQᦪRST*•k=3x2=6.(2)জVW-4Hᐭy=x-1#y=3,Hᐭy=:#y=|,32<3,2•••[\WᑁḄ᦮GḄᙶ᪗M(4,2).ᦑ0ᫀME(4,2).ঝab=1c*def/ḄgGM(1,O),dOPQᦪRSḄgGN(l,6).cᙠx=1hᩩefTᨵ5k᦮GE(1,1),(1,2),(1,3),(1,4),(1,5),x=2c*efx=2d/gG(2,1),dOPQᦪRSgG(2,3),efx=2hᩩfTᙠ[\Wᑁᨵlk᦮G.A02z}~*᪷[\ᑁᨵ6k᦮ᦪGxḄ.⚪ὃ8lqᦪdOPQᦪḄmᔠ⚪*⚪ᐵCBᳮ᦮GḄ*ᑖyFx>2d<2ḄHᐭᦪ᪆r-xḄ.20.ூ0ᫀ௃(1)EAD,OD,•ACM஺஺Ḅe*

19•/.ADC=90°,•^LADO+Z.CDO=90°,•••AB=AC,♦BAD=Z.CAD,•Z.BAC=2(CAD,•^BAC=2CDF,:.Z.CAD=CDF,♦ODC+CDF=90°,:.Z-ODF=90°,OFB஺஺Ḅᑗf(2)E4B=AC,•B=ACD,•,BED=Z-ACD,•BED=B,:.DE=OB(3)WEv/-DAC=Z.CDFZ,F=zF,9•*ADF^LDCF,DFCFCD—=—=—,AFDFAD1vcosB—cosACB-•CD=k,AC=3k,•■AD=y/AC2-CD2=2*,DF_CF_k_\[2=—,AFDF24••CF=2,DF=4Aঝ••.AF=16,•AC=AF-CF=14,:.AO=OC=7,.•஺஺ḄB7.ூ᪆௃(1)4),஺஺,᪷ᙊᕜ<ᳮ#ᑮN/WC=90஺,-#4஺஺+"0஺=90°,᪷ῪḄឋ#ᑮ484஺=^CAD,Hᣚ#ᑮNC4O=CDF,¡B#ᑮ220⚓*ᐳ25⚓

20|(2)᪷ῪḄឋ#ᑮNB=4CD,Hᣚ#ᑮNBED=AB,¡B#ᑮDE=DBব᪷s§Ḅឋ#ᑮ2=ⅉ=©*CD=k,AC=3k,#ᑮAD=y/AC2-CD2=2V2/c.-#4F=16,¡B#ᑮ|.⚪ὃ89ᙊḄmᔠ⚪*ᑗfḄᑨ<*s§Ḅᑨ<°ឋ*ῪḄᑨ<°ឋ*ᙊᑁ±²Ḅឋ*:;<ᳮ*³B´yRB⚪ḄᐵC.21.ூ0ᫀ௃:(1)h15¶·ᜧ¹ᨵ஺¶,ᑣ»¹ᨵ(15-a)¶,12a+8(15-a)=152#*a=8,ᑣ15—a=7,0Eh15¶·ᜧ¹8¶*»¹7¶E(2)ÁÂAÃ╋Ḅᜧ¹Mx¶*ᑣÁÂAÃ╋Ḅ»¹M(10-4)¶*ÁÂBÃ╋Ḅᜧ¹ᨵ(8-Ƕ*ÁÂBÃ╋Ḅ»¹ᨵ7-(10-x)=(%-3)¶*ᵫ⚪Ë#*y=800%+400(10-x)+900(8-x)+600(%-3)=100%+9400,ᓽydxḄᦪᐵ"rMy=100x+9400,•••ÏÂAÃ╋Ḅ■ÑᵨÒÓÔÕ¡100Ö*12%+8(10-%)>100,#*x>5,.•.ax=5c*y#ᨬ»*cy=9900,0EydxḄᦪ᪆ry=100X+9400,Ùᔠ⌕-ḄᨬÕÚᵨM9900ᐗ.ூ᪆௃(1)᪷⚪*Ë>ᐜh15¶·ᜧ¹ᨵ஻¶*ᑣ»¹ᨵ(15-a)¶*ᯠuᓽË#ᑮs@ḄÞß*à,Ë>-#h15¶·ᜧ»¹ᔜâÕ¶(2)᪷(1)·Ḅã°⚪*Ë>#ᑮydxḄᦪᐵ"r*v᪷ÏÂAÃ╋Ḅ■ÑᵨÒÓÔÕ¡100Ö*Ë>#ᑮxḄ*ᯠu᪷lqᦪḄឋ*ᓽË0⚪.⚪ὃ8lqᦪḄ@ᵨஹlᐗlqÞßḄ@ᵨஹlᐗlqÓrḄ@ᵨ*0⚪ḄᐵCB⚪*ᑡ$s@ḄÞß*ᑭᵨlqᦪḄឋ°ÓrḄឋ0.

2122.ூ0ᫀ௃APDPDQ3.63ூ᪆௃E(1)ᙠAP,DP,QQḄ)/hk·*

22ᵫRS#Eyi=ஹ2c*4PḄ)/õM3.63cm.(0ᫀÓöl)ᦑ0ᫀME3.63.(1)᪷éḄ<ᓽË-(2)í⊤ï·ḄᦪðGஹfᓽË#(3)Hᐭ÷øùRSË#|.⚪BúG⚪ḄᦪRS*⚪ḄᐵCBᳮ⚪*ûùR*üýᑭᵨᦪᔠḄþÿὃ⚪ὃὃ⚪.23.ூᫀ௃9010ூ᪆௃(1)•••PACA┐ᔣ60஺ᑮADB,•*ACP^^ABD,/.PAD=60°,AP=AD=6,PC=DB=10,Z.APC=Z-ADB=150°,4DP!"#$%.%AADP=60°,AP=DP=6,•PDB=90°,•PB=y/DB2+DP2=V36+64=10,ᦑᫀ'90஺10(ூ⚪)௃

23(2)F4BC,Z.ACB=90°,sinABC=:.Z-ABC=45°,.AABC=4CAB=45°,•AC—BC,᝞,2,-aACP./C⌮┐90஺ᑮBCD,,2BD=PA=2,CD=CP=3V2.PCD=90°,Z.APC(BDC,••.PCO!Ὺ2$#$%PD=V2PC=V2x3V2=6*PDC=45°=4CPD,vPD2+BD2=36+4=40,PB2=40,•••PD2+BD2=PB2,•••PDB=90°,Z.BDC=135°,•••UPC=135°,vAPC+CPD=180°,/A,/P,/஺#/ᐳ4AD=AP+PD=8,AB=yjAD2+BD2=<64+4=2V17;(3)᝞,5B6BEJL4C,ᚖ8'E9A஺F,/.BAC=45°,•.BE=AE,••C+Z-EBC=90°,zC+Z-EAF=90°,•Z.EAF=EBC,ᙠAFE;BCE,<24⚓ᐳ25⚓

24Z.EAF=(EBCBE=AE,Z.FEA=CEB=90°.AF=BC=BD+DC=10,FBD="AC,>•BDF=ADC=90°,•••BDF~AADCfFD_BD,t•CDAD.?_6,•4-10+AO'ADF=2,AD=12,ABCḄ☢D=FXAD=3x10X12=60.ூ▅Hᩞᧇ௃(1)ᵫḄឋMN4P=AD=6,PC=DB=10,UPC=^ADB=150°,4PAD=60°,NOA4DP!"#$%N440P=60஺AP=DP=6,ᓽNQ(ூ⚪)௃(2)ᵫ┦$#$SᦪNQ4aBe=45஺N4C=BC,-4CP./C⌮┐90஺ᑮBCD,ᵫḄឋMNBD=P4=2,CD=CP=372./PCD=90஺U4PC=BDC,VWXᳮNQA஺ḄZᵫVWXᳮḄ⌮XᳮNQNPDB=90஺ᵫVWXᳮNQABḄZ(ூᮣ\]ᵨ௃(3)᝞,5B6BE_L4C,ᚖ8'E9AOF,ᵫ4BAC=45஺N_ᑮBE=4E,NOAFE=^BCE,N_`IL4F=BC=10,aNF8D=DAC,>N80F=/.ADC=90°,ᵫbN_OcABDFsAADC,N◫=ᘤNQfḄZᓽNQ.g⚪hijᣚlᔠ⚪ὃnoᐰ!#$%ḄᑨXrឋM!"#$%ḄᑨXrឋMst#$%ḄᑨXrឋMVWXᳮ!uvwxាz{|4᪀⌼ᐰ!#$%ᡈst#$%g⚪Ḅᐵ.