2021-2022学年山东省济南市槐荫区九年级（下）开学数学试卷（附答案详解）

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2021-2022
ḕᓭᓭᐶ
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612

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T32=9,9Ḅõö÷-᪷3.ᦑ⌱
A.᪷õö÷-᪷Ḅúûáñ.ü⚪ὃ#þõö÷-᪷Ḅúû6ÿẠ⚪ᭆ⚪Ḅᐵ.2.ூᫀ௃Cூ᪆௃ᙊ┵ḄῪ!"ᨵ$%Ḅᙊ&'A)*ᔠ⚪,-ᙊ.Ḅ/ᙊ&'B)*ᔠ⚪,-123Ḅஹ512&'⌱⚗C*ᔠ⚪,-8.Ḅ/&'஺)*ᔠ⚪,-ᦑ⌱C.᪷<ᙊ┵ஹᙊ.ஹ123ஹ8.Ḅஹᑨ>ᓽ@.A⚪ὃCDᓫFG3ḄᳮḄ,IJKᔜMFG3ḄḄN1Kᑨ>ḄOP.3.ூᫀ௃Bூ᪆௃ூᑖ᪆௃'⚪ὃCSTᦪVḄ⊤X2V.⊤XYᐵ⌕1KK[஺Ḅ\]^”Ḅ\.STᦪVḄ⊤X`aax1(PḄ`ᐸ!1`hi10,஻a᦮ᦪ.K[”Ḅ\Y⌕nopᦪqᡂaYsᦪ%tuvwxy஻Ḅz{\|sᦪ%tuḄyᦪ}h.~pᦪz{\210Y஻1᦮ᦪ.ூ௃21500000ᵨSTᦪV⊤Xa2.15x107,ᦑ⌱B.4.ூᫀ௃Cூ᪆௃AB஻CD,•••/.ADC=^BAD=35°,vAD1AC,•••/.ADC+ACD=90",

8NACC=90°-35°=55°,ᦑ⌱C.ᵫḄឋ4DC=/BAD=35஺ᵫᚖḄ[I@AC஺᪷<ᑁ[ᳮ4CDḄᦪ.A⚪⌕ὃCvḄឋ]^ᑁ[ᳮẠ⚪.5.ூᫀ௃Cூ᪆௃4ஹ){!"{ᦑ'⌱⚗)ᔠ⚪,-8ஹ{)!"{ᦑ'⌱⚗)ᔠ⚪,-Cஹ¡{¢!"{ᦑ'⌱⚗*ᔠ⚪,-஺ஹ¡){£)!"{ᦑ'⌱⚗)ᔠ⚪,-ᦑ⌱C.᪷|a|a+b<0,⌱⚗A┯Ä--a>b,⌱⚗31K-a-b>0,⌱⚗C┯Ä--b>a,⌱⚗஺┯Äᦑ⌱B.᪷<ᦪÅ%ḄyÆᑨ>஺|஺Ḅ1Ç]^z{\ḄᜧsᑭᵨᨵᳮᦪḄÊË}ÌᦪḄ,Iᑨ>ᓽ@.'⚪ὃCvᦪ᪷<ᦪK[஻|ÍḄ1Ç^z{\ᜧsA⚪Ḅᐵ.7.ூᫀ௃Dூ᪆௃ூᑖ᪆௃A⚪⌕ὃCᑖ`ḄÎ◀V,ÐÑÒᑖ`Î◀VḄÓÔVᑣ⚪Ḅᐵᐜᑖ×&`ᑖ

9◀V¨ᓄaÎV«Ùᑖᓽ@.ூ௃p`=ᔩ2.!=Ûa-oaobᦑ⌱D.8.ூᫀ௃Bூ᪆௃ூᑖ᪆௃ὃC!yᦪஹÔÜᙳᦪḄÞÔ2V$ßᦪ<àsᑮᜧ᣸ᑡ«ᜐᙠ!æyÆḄ$¤ᦪᡈº¤ᦪḄᙳᦪ³²ßᦪ<Ḅ!yᦪᙳᦪᑣÌ᧜$ßᦪ<Ḅé!ê.²7¤ᦪ<àsᑮᜧ᣸ë«ᜐᙠì4yḄᦪ!yᦪᑭᵨÔÜᙳᦪḄÞÔí`ÞÔᓽ@.ூ௃o²7¤ᦪ<àsᑮᜧ᣸ᑡᜐì4yḄᦪ9.7m,&'!yᦪ9.7m,ᙳᦪa(9.5+9.6+9.7+9.7+9.8+10.1+10.2)+7=9.8m,ᦑ⌱B.9.ூᫀ௃Dூ᪆௃•.Ìïðñᦪy=5(òÍ0)óḄº¤ᑖôᑖõyì$ஹó▲■■k>0,—fc<0,÷$øñᦪy=/cr—kḄóᙠì$ஹஹùó▲ᦑ⌱D.᪷<ÌïðñᦪḄóឋ@k>0,à@ᑨ>-k<0,ᯠ«ᑨ>$øñᦪy=kx—kḄóᡠᙠó▲ᓽ@.'⚪⌕ὃCvÌïðñᦪḄóឋ$øñᦪó|ýᦪḄᐵýᐵÑÒÌïðñᦪy=[,~k>0,þÿḄᑖஹ▲ᙠ▲ᑁyxḄᜧ.10.ூᫀ௃Dூ᪆௃ᵫ!"#E$ᚖ&'ᑖAB,•••MB=MA,BM+MD=MA+MD,()M4ஹDA,᝞+,

10MA+MD>4஺/0120M3ᙠAO456789MA+MDḄᨬ;3AD1BC,1.s4ABe=^-BC-AD=10,.„10x2•••AD=:?:=5r,4BM+MD@AḄᨬ;<5.ᦑ⌱D.ᵫDE!+#ᑮ#EFᚖ&'ᑖA8,ᑣMB=M4,ᡠIBM+MD=M4+MD,()MAஹDA,᝞+ᑭᵨ3LMNᨬOPᑨRM2+MDḄᨬ;ὃὃ⚪.✌ᐜVA஺$wVaAC,£>/ᓽP⚪.ூ௃FDLEB,ACLEB,•••DF//AC,■AF//EB,VACD$w'VvZ.ACD=90°,

11VAC஺$wV•-DF=AC,ᙠ>vZ.ACB=90°,AC=AB-sin43°«1.6x0.7=1.12(m),ADF=AC=1.12(m),ᙠRtADEF,vZ.FDE=90°,᝞DF•tanNEf112/.DE4=2.8(m),ᦑ⌱B.12.ூᫀ௃A2m—6<02m-6—Q_~-L{4(m23)(2m6)2>.3#?0,#?n>3,¡4ᡠ¢£¤ᩩ¥Ḅ஻Ḅ;ὃ⌱½⚪>Ḅ¾⚪.13.ூᫀ௃0—2)2ூ᪆௃:À^=0-2)2,ᦑᫀ<(m-2)2À^ᑭᵨÁᐰ'Ã]^ᑖᓽP.Ä⚪ὃefÅ^ᑖ-|ᵨ]^"hijkÁᐰ'Ã]^wE⚪Ḅᐵv.14.ூᫀ௃|ூ᪆௃ᐳᨵᳫ3+2=5pÊᳫᨵ2pÅÄ᥎aḄᳫwÊᳫḄᭆ᳛<I

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143⚪o⌕ὃ6qMLḄឋsᢚPḄឋs^_ᳮ%tuvuLḄឋsᐵA@ᑭᵨ^_ᳮᑡij.19.ூᫀ௃%wl-2xg+2+2=1-14-2+2=4.ூ%᪆௃tFᑭᵨx᦮ᦪᢣᦪ{Ḅឋs|}~ᢣᦪᗩḄឋseQᑖ$ᓄᫀ.⚪o⌕ὃ6qᦪᓄᔜᦪ@%⚪ᐵA.3(%-1)>2x-5020.ூᫀ௃%:2%ீঝ%VeজXN-2,%Veঝx1522.ூᫀ௃%1\]EF0C,᝞²,:.Z.OCD=90°,Z.ACD+Z.ACO=90°,vAD1DC,Z.ADC=90°,4ACD+4LMC=90°,•••Z-ACO=Z.DACf••OA=OC,•Z-OAC=Z.OCAf•Z.DAC=Z.OAC,4C@⊈BḄuᑖ§ফ./8@஺஺Ḅt´஻CB=90°,.Z.D=R4cB=90°,••Z.DAC=Z.BAC,•RtADCsRtACB,ADAC:.—=—ACAB:.AC2=AD-AB=2x3=6,:.AC=V6.ூ%᪆௃1EFOC,᪷,ᑗ§Ḅឋs'NOCO=90°,᪷,4஺1DC,"·´§¸ᓽ'\]AC@4MBḄuᑖ§2ᑭᵨᙊᕜuᳮᑮR4cB=90°,\]RtZiAnCsRtAACB,¦:Kᡂ¼½ᓽ'4cḄ¾.3⚪ὃ6qᑗ§ḄឋsᙊḄᑗ§ᚖt©ÀbᑗªḄ·´ÁÂᙊḄᑗ§ÃEbᑗªḄ·´᪀⌼ᳮ²ᚖtᐵ.Æὃ6qᙊᕜuᳮ.

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ᑖaஹ஻,3000a+3500b=32000((3400-3000)a+(4000-3500)8=4400'*=1S=4

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10BḄ
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