1、人教版数学七年级上册期末计算题100例附解析(8)1.化简再求值: (a+2b)(2ab)(a+2b)2(a2b)2 ,其中 a=13,b=32.计算:(1)简便计算: 15341614(2)计算: 2a3b2(3bc2)3(ca2)(3)先化简再求值: (3x+2y)(3x2y)(x+2y)(5x2y)4x ,其中x= 12 ,y=23.化简: (1)(2 13 ) (2)(0.25); (3)(a) (4)(2.8); (5)(1); (6)(5) 4.计算:(-14)-(+15) 5.计算题 (1)49+(-23)+(-35) (2)19-(-76)-22-(-52) (3)1.6+3.
2、20.4+1.8 (4)7+(5)(2) . 6.利用等式的性质解方程:3x+6=312x7.计算: (3)56(145)(14) 8.计算 (1)3+87 ; (2)236(3)+2(4) ; (3)(24)(131816) ; (4)(37)0.125(213)(8) ; 9.2(1-2x)=x-8 10.计算: (1)(16 34 )(10 14 )(+1 12 ) (2)( 34 )(1 12 )(2 14 ) (3)(2)26(2)34 (4)(4a2b5ab2)(3a2b4ab2) 11.先化简,再求值: 12 x2(x 13 y2)+( 32 x+ 13 y2),其中x,y满足|
3、x6|+(y+2)2=0 12.先去括号,再合并同类项4a2+2(3ab2a2)(7ab1)13.计算:(2)34(5) 12 14.计算:(1)8(2)(+3)+(1)(2)(12)(+4)(2)(3)(3)2334+11224(4)339323+23 15.计算: (1)(1456+23)(24) (2)12019+(2)245+|122| 16.解方程 (1)2(2x+1)=10x+7 (2)3-2(x+1)=2(x-3) 17.解方程: (1)62x=3x4 ; (2)322(x23)+43=1 18.化简: (2x212+3x)4(xx2+12) 19.解下列各题: (1)计算: (
4、2)0(14)2+(4)2020(14)2020 (2)计算:(2a+5)(2a5)4a(a2) (3)用乘法公式计算:2019220182020 20.合并同类项:4a2+3b2+2ab4a26b2 21.计算: (1)(-5.5)+(-3.2)-(-2.5)-4.8 (2)-40-28-(-19)+(-24) (3)(23112115)(160) (4)14(10.5)132(3)2 22.计算 (1)(4)(+13)+(5)(9)+7 (2)6143.3(6)(334)+4+3.3 (3)81(214)49(16) (4)(24)(138+2130.75) 23.计算:12+34+56+
5、20072008+20092010+201124.计算: (1)(1813+16)(24) ; (2)|2|(1)20133122 ; (3)12(10.5)132(3)2 ; (4)7(36)(87)16 25.计算与化简: (1)4|6|3 (13) ; (2)32+(1)2001 16 +(5)2; (3)2x2y2(3xyx2y)xy; (4)6a2b2ab23(a2b2ab2). 26.计算: (1)a3a2a (2)(x3)2+(x2)3xx5 27.计算: (1)5(2) (2)16 +( 13 ) (3)3 313 (4)34(-43)-265 . 28.“*”是规定的一种运算
6、法则: ab=a2b2 ,求 5(1)2 的值。 29.计算: (1)(-5)+(+7)-(-3)-(+20) (2)25 56 ( 25 )+(-2)(-1)2019 30.计算下列各题: (1)(-12)-5+(-17)-(-13) (2)( 16+58712) (-24) (3)4212019515+17+21 31.先化简,再求值: 2ab+3a2b2(a2bab) ,其中 a=1,b=2 32.计算: (1)5 14 (2 23 )+(3 14 )(+4 23 ) (2)( 34 58 + 912 )(24) (3)(3) 34 43 (15) (4)14+|(2)310|(3)(1
7、)2017 33.计算: 22+30121a2a4+(a2)334.若 |x+2| 与 |12y| 互为相反数,求 x+y 的值. 35.计算: (1)25 |1 12 |(+2 14 )(2.75) (2)141(10.5 13 )6 36.解方程: 12y=122y 37.计算 (1)(3mn+1)(3mn1)8m2n2 (2)(x+2)2(x+1)(x1) (3)(x+y)2(xy)22xy 38.解下列方程 (1)4x = 20 (2)6x + 6=18 (3)5x 6 = 24 (4)3x - 9 = 3 39.若|a|=7,|b|=3,且ab0,求a+b的值 40.解方程: 7x3
8、=5x+9 41.计算: (1)16(2)3( 18 )(4) (2)12( 12 23 ) 13 2+(3)2 42.计算: (1)(12ab)(23ab22ab+43b) (2)(2xy)(2xy)(xy)22(2x2xy) 43.解方程:2 2x+13 = 1+x2 44.解方程 (1)3(x2)=2x5 (2)x33=x3x16 45.解下列方程: (1)x12 4x3 1 (2)0.1x0.20.02 x+10.5 3. 46.先化简再求值:14(-8x2-16y)-13(3x2-9y) ,其中x=12,y=14 47.计算: (1)12(18)+(7)15 (2)16+(-25)+
9、 24 +(+25) 48.先化简再求值:已知多项式A=3a26ab+b2 , B=2a2+3ab5b2 , 当a=1,b=1时,试求A+2B的值49.计算下列各题: (1)(3.14-)0+(-1)2019+3-2 (2)(m+1)2-m(m+3)-3 50. (1)先化简,再求值:x2+2x3(x2 23 x),其中x= 12 (2)计算: 12 xy2(xy 13 xy2)+( 32 xy+ 13 xy2),其中x、y满足|x6|+(y+2)2=0 51.计算: (1)(+3)(5) (2)(-1)2016+(-2)(-3)+(-2)3 52.计算 (1)(14131)(12) (2)2
10、214+(3)3(827) 53.当x取何值时,代数式3x5与4x+6的值互为相反数 54.计算 (1)13+7(20)(40)6 (2)0.5+( 14 )2.75+( 12 ) (3)(12)5+(14)(39) (4)25 |1 12 |(+2 14 )(2.75) (5)(423)(0.5312) (6)0.474 56 (1.53)1 16 55.计算: (1)5(4)+78 (2)312(35)15 (3)14(3)2|49| (4)(5)(325)+(7)32512(325) 56.计算: (1)2x5(2x)3(x2)3(7x)2 (2)12016+(2)2(3.14)0(23
11、)1 (3)(a2b)2(a+2b)2 (4)(mn)(4mn)+3m(4mn) 57.先化简,再求值: ,其中a3,b1 58.计算:-32(5-3)-(-2)2l-4l 59.计算: (1)0(8)108; (2)6 23 32 ; (3)2.5 58 (14) ; (4)(35) (312) (114) 3. 60.计算:(1)(aam+1)2(a2)m+3a2(2)(13)2+0.22016(5)2015(12)0(3)求代数式 (2a+b)2(3ab)(3a+b)+5a(ab) 的值,其中 a=2 , b=12 61.解方程: (3x2)+2(x1)=1 62.已知|a|=4,b2=
12、9,且ab0,求a-b的值 63.先化简,再求值:3(2a2+ab)-2(3a2+ab),其中a=-2,b=3。 64.计算下列各题: (1)(+5)3(6) ; (2)(232+16)(32)(13)2518 65.解下列方程: (1)4x3(12x)6x2(8x) (2)2x13 2x34 1 66.计算: (1)12+(-7)-(-15) (2)4+(-2)35-(-0.28)4 67.先化简,再求值: 5(3a2bab2)4(ab2+3a2b) ,其中 a=12 , b=13 . 68.4ab(-3a2b2)+(2ab)3 69.解方程 (1)2x=9x ; (2)2x+135x16=
13、1 . 70.先化简,再求值:2(2x-3y-1)- 13 (9x+6y-6),其中x=2,y=-0.5. 71.计算: (1)-14- 16 2-(-3)2(-7); (2)(1 12 - 58 + 712 )(- 124 )-8(- 12 )3 72.计算: (xy3)(x+y3) 73.解方程: (1)3x-2=1-2(x+1); (2)x+45+1=xx53 . 74. 计算: (1)(1)0(12)11.252017(45)2018 (2)(2xy)2(2x+y)(2xy)+4xy2y 75.计算 (1)3627( 73 119 + 227 ) (2)72+2(3)2(6)(13)2
14、 76.计算: (1)-1.51.4- (-3.6)-1.4; (2)7347(83) ; (3)|-2|( 12 )(-5)(-2); (4)(2312+56)(24) 77.计算:-14-(-6)+3(- 13 ) 78.计算25112+2142.7579.计算: (1)(3x2)2(4y3)(6xy)2; (2)(2xy)(2x+y)+y(y6x)2x 80.用简便方法计算下列各题 (1)(45)2015(1.25)2016 (2)(318)12(825)11(2)3 81.计算: (1)(214)(+58)+(14)(18) (2)9(4)2(2) 82.化简求值:已知:(x3)2 +
15、|y+13| =0,求3x2y2xy22(xy 32x2y )+3xy+5xy2的值 83.计算下列各式:(1)(1.25)+(+5.25)(2)(7)+(2)84.先化简,再求值: (2a+3b)(2a3b)(2ab)2(4b) ,其中 a=52 , b=1.85.计算: (+26)+(18)+516 151(420) 18(23)+1323423 8(45)|16| (4719+221)(63) (34)38(916)(18) 86.解方程: (1)2x=3x+8 ; (2)x3x14=x6 . 87.先化简,再求值:(4x3)(x2)2(x1)(2x3),x2; 若(x2pxq)(x23
16、x2)的结果中不含x3和x2项,求p和q的值.88.解方程: (1)34x+1=7 (2)322(x+13)+23=5x 89.解方程: 3y+14=22y13 90.计算下列各题 (1)319(9)+681(9) ; (2)(2131316)78 ; (3)32|(5)3|(25)218|(3)2| (4)422(13)+(3)3214(23)2 . 91.解方程: (1)x4=25x (2)5(x+8)=6(2x7)+5 (3)x74 2x123 =1 (4)0.50.2x0.2 =0.1+ x0.5 92.解方程: (1)5-2x=9-4x (2)2x13 =1- 5x+76 93.解方
17、程: (1)4x=5x5 (2)4x+3(2x3)=12(x4) (3)x+241=2x36 (4)0.2x0.10.310x+16=0.02x+0.010.04214 94.已知m是8的相反数,n比m的相反数小2,求n比m大多少? 95.若|a|=21,|b|=27,且|a+b|=-(a+b),求a-b的值 96. 计算: (1)5 14 -(-2 23 )+(-3 14 )-(+4 23 ); (2)(- 3458+912 )(-24); (3)(-3) 34 43 (-15); (4)-14+|(-2)3-10|-(-3)(-1)2017 97.计算: (1)14+12(13)(2)3
18、; (2)(34+5678)(24) 98.已知1- 12 = 12 , 12 - 13 = 16 , 13 - 14 = 112 , 14 - 15 = 120 根据这些等式求值。请你仔细观察,并找出其奥妙,再计算: 112+123+134+14950 99.计算: (1)3+8715 (2)20+(14)(18)13 100. (1)( 34 16 38 )(24); (2)22+12(3)2(3) (3)( 56 )|1 23 |+(2)3(1.5) 答案解析部分1.答案解: (a+2b)(2ab)(a+2b)2(a2b)2=2a2ab+4ab2b2a24ab4b2a2+4ab4b2=
19、当a=- 13 ,b=-3时,原式=-87 2.答案:(1)解: 15341614 .=(16- 14 )(16+ 14 ).=162-( 14 )2.=256- 116 .=255 1516.(2)解: 2a3b2(3bc2)3(ca2) = 2a3b2(27b3c6)(ca2) =-54a3b5c6(ca2).=54ab5c5(3)解:原式 =(9x24y2)(5x2+8xy4y2)4x .=(4x28xy)4x .=x2y.当x= 12 ,y=2时,原式= 72.3.答案:(1)解:(2 13 )2 13(2)解:( 0.25)0.25(3)解:(a)a(4)解:(2.8)2.8(5)解
20、:(1)(1)1(6)解:(5)(5)5 4.答案解:(-14)-(+15) =-14-15=-(14+15) (符号后面添括号,括号里面的数要变号)=-295.答案:(1)解:原式 =4958 =9(2)解:原式 =19+7622+52=14722=125(3)解:原式 =(3.2+1.8)(1.6+0.4)=52=3(4)解:原式 =75+2=12+2=106.答案解:3x+6=312x两边同时加上(2x6),得:3x+6+2x6=312x+2x6即:5x=25两边同时除以5,得:x=57.答案解:原式=-3569514=-98 8.答案:(1)解: 3+87 =37+8 =10+8 =2
21、 ;(2)解: 236(3)+2(4) =8+188 =18 ;(3)解: (24)(131816) =13(24)18(24)16(24) =8+3+4 =1 ;(4)解: (37)0.125(213)(8) =(37)(73)(8)0.125 =1 9.答案解:2-4x=x-8,-4x-x=-8-2,-5x=-10,x=210.答案:(1)解:原式=16 34 +10 14 1 12=8(2)解:原式= 34 32 49= 12(3)解:原式=46(8)4=24+2=26(4)解:原式=4a2b5ab23a2b+4ab2=a2b5ab211.答案解:原式= 12 x2x+ 23 y2+ 3
22、2 x+ 13 y2=y2 , |x6|+(y+2)2=0,x=6,y=2,则原式=412.答案解:4a2+2(3ab2a2)(7ab1)=4a2+6ab4a27ab+1=ab+113.答案解:原式=84(5)2=32+10=22 14.答案解:(1)原式=8+231=104=6;(2)原式=36=9;(3)原式=16+182=18+18=0;(4)原式=27(9)2+(8)=3(6)=3+6=915.答案:(1)解:原式 =6+2016=2(2)解:原式 =1+5+3=7 16.答案:(1)解:解去括号得:4x+2=10x+7 移项合并得:-6x=5解得:x= -56 (2)解:去括号得:3
23、-2x-2=2x-6 移项合并得:-4x=-7解得:x= 74 17.答案:(1)解: 5x=10 x=2 (2)解: 3(x23)+2=1 3x=1 x=13 18.答案解:原式=2x2-12+3x-4x+4x2-2=6x2x52 19.答案:(1)原式= 116+(414)2020 =-14;(2)原式= 4a2254a2+8a = 8a25 ;(3)原式=20192(2019-1)(2019+1) = 2019220192+1 =120.答案解:4a2+3b2+2ab4a26b2=4a24a2+3b26b2+2ab=3b2+2ab21.答案:(1)解:原式=-5.5-3.2+2.5-4.
24、8, =-(3.2+4.8)-(5.5-2.5),=-8-3,=-11(2)解:原式=-40-28+19-24, =-73.(3)解:原式= (23112115)(60) = 23 (-60)- 112 (60) - 115 (-60),=-40+5+4,=-31(4)解:原式=-1- 12 13 (-7), =-1+ 76 = 16 22.答案:(1)解: (4)(+13)+(5)(9)+7 =(4135)+(9+7) =22+16 =6 (2)解: 6143.3(6)(334)+4+3.3 =6143.3+6+334+4+3.3 =(614+334)+(3.3+3.3)+(6+4) =10
25、+0+10 =20 (3)解: 81(214)49(16) =81(49)49(116) =3649(116) =16(116) =1 (4)解: (24)(138+2130.75) =(24)118+(24)73(24)34 =33+(56)(18) =71 23.答案解:12+34+56+20072008+20092010+2011=1+(2+3)+(4+5)+(6+7)+(2006+2007)+(2008+2009)+(2010+2011)=1+=1+1005=1006 24.答案:(1)解:原式 =18(24)13(24)+16(24) =3+84 =1 (2)解:原式 =2(1)31
26、22 =262 =212 =14 (3)解:原式 =12121352 =1121325 =1256 =316 (4)解:原式 =7(87)(36)16 =7(87)(36)16 =(8)(6) =48 .25.答案:(1)解:原式46+1 1;(2)解:原式916+25 96+2510;(3)解:原式2x2y6xy+2x2yxy 4x2y7xy;(4)解:原式6a2b2ab2+3a2b6ab2 9a2b8ab2.26.答案:(1)解:a3a2a=a3+2+1=a6(2)解:(x3)2+(x2)3xx5=x6+(x6)x6=x6 27.答案:(1)解:原式=5+2=7(2)解:原式= 16 13
27、 = 16(3)解:原式=3 13 13 = 13(4)解:原式=1 53 = 83 28.答案解:解:a*b=a2-b2 , (-1)*2=(-1)2-22=1-4=-3,5*(-3)=52-(-3)2=25-9=16.29.答案:(1)解:(-5)+(+7)-(-3)-(+20) =-5+7+3- 20=-25+10=-15(2)解:25 56 ( 25 )+(-2)(-1)2019 =25 65 ( 25 )+(-2)(-1)=-12+2=-1030.答案:(1)解:原式= 12+5+17+13= -34+13= -21(2)解:原式= 1624+582471224= 4+(-15)-(
28、-14)= 4+(-15)+14= (3)解:原式= 1611515+4= 16125+4= 12+125= 112425.31.答案解:原式=-2ab+3a2b-2 a2b+2ab=-2ab+2ab+3 a2b-2 a2b= a2b;当 a=1,b=2 时,原式=(-1)2(-2)= -2 32.答案:(1)解:原式=5 14 +2 23 3 14 4 24 =5 14 3 14 +2 23 4 23 =22=0(2)解:原式= 34 24+ 58 24 912 24 =18+1518=15(3)解:原式=(3) 43 43 (15) =445=80(4)解:原式=1+|810|(3)(1)
29、 =1+183=1433.答案解:(1)原式=-4+1+2=-1;(2)原式=a6+a6=2a6.34.答案解:因为|x+2|与|1-2y|互为相反数, 所以|x+2|+|1-2y|=0,所以|x+2|=0,|1-2y|=0,即x+2=0,1-2y=0,所以x=-2,y= 12 .所以x+y=-2+ 12 =- 32 35.答案:(1)解:原式=0.41.52.25+2.75=0.43.75+2.75=0.41=0.6(2)解:原式=1(11+ 16 )6=11=2 36.答案解:移项: 12y+2y=12 , 合并同类项: 52y=12 ,化系数为1: y=15 37.答案:(1)解:原式=
30、9m2n218m2n2=m2n21(2)解:原式=x2+4x+4x2+1=4x+5(3)解:原式=(x2+2xy+y2x2+2xyy2)2xy=4xy2xy=2 38.答案:(1)解:系数化为1得 x=5(2)解:移项得 6x=186 , 系数化为1得 x=2 (3)解:移项得 5x=24+6 , 系数化为1得 x=6 (4)解:移项得 3x=3+9 , 系数化为1得 x=4 39.答案解:|a|=7,|b|=3,且ab0,a=7,b=3,或a=7,b=3,a+b=7+3=10或a+b=1040.答案解: 7x5x=9+3, 2x=12 x=6 41.答案:(1)解:16(2)3( 18 )(
31、4) =16(8) 12 =2 12 =2 12 (2)解:12( 12 23 ) 13 2+(3)2 =1+ 16 13 2+9=1+ 12 7= 52 42.答案:(1)解: (12ab)(23ab22ab+43b) = 13a2b3+a2b223ab2 (2)解:(2xy)(2xy)(xy)22(2x2xy) =4x2-y2+x2+2xy+y2-4x2+2xy=x2+4xy. 43.答案解:去分母得,122(2x+1)=3(1+x),去括号得,124x2=3+3x,移项得,4x3x=312+2,合并同类项得,7x=7,系数化为1得,x=144.答案:(1)3(x-2)=2x-5 解:3x
32、-6=2x-5x=1(2)x33=x3x16 解:2(x-3)=6x-(3x-1)2x-6=6x-3x+1x=-745.答案:(1)解: 3(x1)=8x+6, 3x3=8x+6, 3x8x=6+3,5x=9,x=95. (2)解: 5x102(x+1)=3,5x102x2=3, 3x=15, x=5. 46.答案解:14(-8x2-16y)-13(3x2-9y)=-2x2-y-23y=-3x2-当=12,=14时,-32-=-(12)-14-47.答案:(1)解:原式=12+18+(-7)+(-15) =(12+18)+(-7)+(-15) =30+(-22) =30-22 =8(2)解:原
33、式=16+(-25)+24+25 =(16+24)+(25-25) =40+0 =40 48.答案解:A+2B=3a26ab+b2+2(2a2+3ab5b2)=3a26ab+b24a2+6ab10b2=a29b2 , 当a=1,b=1 时原式=129(1)2=1049.答案:(1)解: 原式=1-1+19=19; (2)解: 原式=m2+2m+1-m2-3m-3=-m-2 50.答案:(1)解:原式=x2+2x3x2+2x=2x2+4x,当x= 12 时,原式= 12 2=2 12(2)解:原式= 12 xy2xy+ 23 xy2+ 32 xy+ 13 xy2=xy2 , 由|x6|+(y+2
34、)2=0,得到x=6,y=2,则原式=2451.答案:(1)解:原式 =3+5=8(2)解:原式 =1+68=1 52.答案:(1)解:原式= 14(12)13(12)1(12) = 3+4+12 =13(2)解:原式= 414+(27)(827) = 1+8 =753.答案解:根据题意,得:3x5+(4x+6)0, 去括号,得:3x54x+60,移项,得:3x4x56,合并同类项,得:x1,系数化为1,得:x154.答案:(1)解:原式=13+7+20+406=74(2)解:原式=0.5 12 14 2.75=3(3)解:原式=12514+39=8(4)解:原式= 25 1 12 2 14
35、+2.75= 35(5)解:原式=4 23 +3 12 0.5=1 23(6)解:原式=0.47+1.534 56 1 16 =26=4 55.答案:(1)解:5(4)+78, =5+4+78, =2(2)解: 312(35)15 , = 7213515 , = 150(3)解: 14(3)2|49| , = 1949 , =14, =-5(4)解: (5)(325)+(7)32512(325) , = 53257325+12325 , = 325(57+12) =34 56.答案:(1)2x5(2x)3(x2)3(7x)2 = 2x5(8x3)+x649x2 = 16x8+49x8 = 33
36、x8 (2)12016+(2)2(3.14)0(23)1 = 1+14132 = 134 (3)(a2b)2(a+2b)2 = (a2b)(a+2b)2 = (a24b2)2 = a48a2b2+16b4 (4)(mn)(4mn)+3m(4mn) = (4mn)(mn+3m) = (4mn)(4mn) = 16m28mn+n2 57.答案解:原式2ab3a4a2b2ab a2b当a3,b1时,原式321158.答案解:原式=-92-44 =-18-1=-1959.答案:(1)解:原式0(2)解:原式6 32 32 272(3)解:原式 52 85 (14) 1(4)解:原式 35 72 45
37、13 1425 60.答案:(1)解:原式= a2a2m+2a2m+6a2=a2m+4a2m+4 =0.(2)解:原式= 9+(50.2)20150.21 =90.21=7.8.(3)解:(2a+b) (3ab)(3a+b)+5a(ab)=4a+4ab+b9a+b+5a5ab=ab+2b,当a=2、b= 12 时,原式= 32.61.答案解: 3x2+2x2=1 ,3x+2x=1+2+2 ,x=162.答案解:|a|=4,b2=9,a=4,b=3,又ab0,a、b同号,当a=4,b=3时,a-b=4-3=1;当a=-4,b=-3时,a-b=-4-(-3)=-1;综上所述:a-b的值为1或-1.
38、 63.答案:解:3(2a2+ab)-2(3a2+ab)=6a2+3ab-6a2-2ab=ab, 当a=-2,b=3时,原式=-23=-664.答案:(1)解:原式=5-3+6=8;(2)解:原式= 2(32)32(32)+16(32)19185 = 3+941425 = 75 65.答案:(1)解:4x3(12x)6x2(8x)4x36+3x=6x16+2x4x+3x-6x-2x=16+36-x=20x20(2)解:4(2x-1)-3(2x-3)=128x-4-(6x-9)=128x-6x=12+4-92x=7x 72 66.答案:(1)解:原式 =127+15=277=20; (2)解:原
39、式 =485+0.7=440+0.07=35.93. 67.答案解:原式化简= 3a2bab2 代入求值= 1136 68.答案解:原式 =12a3b3+8a3b3 =4a3b3 69.答案:(1)解:移项,可得:2xx9, 合并同类项,可得:3x9,系数化为1,可得:x3;(2)解:去分母,可得:2(2x1)(5x1)6, 去括号,可得:4x25x16,移项,合并同类项,可得:x3.70.答案解:原式=4x-6y-2-3x-2y+2 =x-8y把x=2,y=-0.5代入x-8y, 得2-8(-0.5)=2+4=671.答案:(1)解:原式= 11629(7) = 116(7)(17) = 1
40、16 = 76(2)解:原式= (3258+712)(24)8(18) =-36+15-14+1=-34 72.答案解:原式= (x3y)(x3+y) = (x3)2y2 = x26x+9y2 73.答案:(1)解:3x-2=1-2(x+1), 3x-2=1-2x-2,5x=1,x=15 ;(2)解: x+45+1=xx53 , 3(x+4)+15=15x-5(x-5),3x+12+15=15x-5x+25,7x=2,x= 27 .74.答案:(1)解:原式=1+2 45 ( 54 45 )2017=1+2 45 =2 15(2)解:原式=(4x24xy+y24x2+y2+4xy)2y=(2y
41、2)2y=y 75.答案:(1)解:原式=36-63+33-2=4(2)解:原式=49+29-(-6)9=-49+18+54=-31+54=2376.答案:(1)解:原式 =1.5+1.4+3.61.4=2.1 ;(2)解:原式 =43(38)=12 ;(3)解:原式 =2(2)+10=4+10=6 ;(4)解:原式 =(4636+56)(24)=1(24)=24 77.答案解:原式=-1+6+(-1) =478.答案解:25112+2142.75 , =25112214+2.75,=1.12.25+2.75,=3.35+2.75,=0.679.答案:(1)解:原式(9x4)(4y3)(36x
42、2y2) =-36 x4y3(36x2y2)x2y;(2)解:原式(4x2y2+y26xy)2x (4x26xy)2x2x3y80.答案:(1)解: (45)2015(1.25)2016= (45)2015(54)2016(54)= 45(54) 2015( 54 )=1( 54 )= 54(2)解:原式= 258 ( 258 )11( 825 )11(8)=25 (258825)11=2581.答案:(1)解: (214)(+58)+(14)(18)= (94)58+(14)+18= (94+14)+(58+18)=5212=3 ;(2)解: 9(4)2(2)=316(2)=3+8=11 8
43、2.答案解:(x3)2 +|y+13| =0,x3=0,|y +13 |=0,解得x=3,y= 13 ;3x2y2xy22(xy 32x2y )+3xy+5xy2=3x2y2xy2+2xy2 32x2y 3xy+5xy2=3x2y2xy2+2xy3x2y3xy+5xy2=3xy2xy=33 (13)2 3( 13 )=1+1=2.3x2y2xy22(xy 32x2y )+3xy+5xy2的值是283.答案:解;(1)(1.25)+(+5.25)=5.251.25=4;(2)(7)+(2)=(7+2)=784.答案解:原式=(4a26ab+6ab9b24a2+4abb2)(-4b).=(4ab1
44、0b2)(-4b).=4ab(-4b)10b2(-4b).= a+52b ,当a= 52 ,b=-1时,原式= 52 52 =5. 85.答案解: (+26)+(18)+516 =26-18+5-16=-3 151(420) =-15-15=-30 18(23)+1323423 =-12+ 263 - 83 =-12+6=-6 8(45)|16| =- 325116 = -25 (4719+221)(63) =-36+7-6=-35 (34)38(916)(18) = 932(169)(18) = -116 86.答案:(1)解: 2x=3x+8 移项,得: -x3x=8-2 合并同类项,得:
45、 4x=6 系数化为1,得: x=32 (2)解: x3x14=x6 去分母,得: 12x-3(3x1)=2x 去括号,得: 12x-9x+3=2x 移项,得: 12x-9x-2x=-3 合并同类项,得: x=-3 87.答案解:(4x3)(x2)2(x1)(2x3), = 4x28x+3x62(2x23x2x+3) ,= 4x25x64x2+10x6 , = 5x12 x2,原式=-10-12=-22;(x2pxq)(x23x2),= x43x3+2x2+px33px2+2px+qx23qx+2q ,= x4+(p3)x3+(23p+q)x2+(2pq)x+2q ,结果中不含x3和x2项,
46、p3=0 , 23p+q=0 ,p=3,q=7.88.答案:(1)解: 34x+1=7 去分母得, 3x+4=28 移项,合并同类项得, 3x=24 系数化为1,得: x=8 (2)解: 322(x+13)+23=5x 去括号得: 3(x+13)+1=5x 3x+1+1=5x 移项,合并同类项得, 2x=2 系数化为1,得: x=1 89.答案解:去分母,得3(y+1)=244(2y1),去括号,得9y+3=248y+4,移项,得 9y+8y=24+43,合并同类项,得17y=25,系数化为1,得y= 2517 90.答案:(1)解:原式 =(319+681)(9)=1000(9)=9000.
47、(2)解:原式 =(2137813781678)=(122613)=(27)=27.(3)解:原式 =91254251819=9202=31. (4)解:原式 =44(13)+(27)4949=4+43163=163163=0. 91.答案:(1)解:移项,得:x+5x=2+4, 合并同类项,得:6x=6,解得x=1(2)解:去括号,得:5x+40=12x42+5, 移项,合并同类项,可得:7x=77,解得x=11(3)解:去分母,可得:3(x7)4(2x12)=12, 去括号,可得:5x+27=12,移项,合并同类项,可得:5x=15,解得x=3(4)解:去分母,可得:5(0.50.2x)=
48、0.1+2x, 去括号,可得:x+2.5=0.1+2x,移项,合并同类项,可得:3x=2.4,解得x=0.892.答案:(1)5-2x=9-4x -2x+4x=9-52x=4x=2;(2)2x13 =1- 5x+76 2(2x-1)=6-(5x+7)4x-2=6-5x-74x+5x=6-7+29x=1x= 19 93.答案:(1)解:4x=5x54x5x=5,则x=5,解得:x=5(2)解:去括号得,4x+6x9=12x+4,移项得,4x+6x+x=12+4+9,合并同类项得,11x=25,系数化为1得,x= 2511(3)解: x+24 1= 2x36去分母得:3(x+2)12=2(2x3)
49、,去括号得:3x+612=4x6,移项得:3x4x=66+12,合并同类项得:-x=0系数化为1得:x=0(4)解:去分母得,4(2x1)2(10x+1)=3(2x+1)27,去括号得,8x420x2=6x+327,移项得,8x20x6x=327+4+2,合并同类项得,18x=18,系数化为1得,x=194.答案解:m是8的相反数,m=8,n比m的相反数小2,n=(8)2=6,nm=6(8)=14,故n比m大1495.答案解:|a|=21,|b|=27,a=21,b=27,又|a+b|=-(a+b),a+b0,a=21,b=-27,当a=21,b=-27时,a-b=21-(-27)=48;当a
50、=-21,b=-27时,a-b=-21-(-27)=6;综上所述:a-b的值为48或6. 96.答案:(1)解:原式=5 14 +2 23 3 14 4 23=5 14 3 14 +2 23 4 23=22=0;(2)解:原式= 34 24+ 58 24 912 24=18+1518=15;(3)解:原式=(3) 43 43 (15)=445=80(4)解:原式=1+|810|(3)(1)=1+183=1497.答案:(1)解: 14+12(13)(2)3 1+12(3)(8) , =1+1211(2)解: (34+5678)(24) (34)(24)+56(24)(78)(24) , =1820+211998.答案解: 112+123+134+14950 = 112+1213+1314+149150 = 1150 = 4950 99.答案:(1)解:原式=25+8=17;(2)解:原式=2014+1813=47+18=29 100.答案:(1)解:( 34 16 38 )(24); (18)+4+9,5(2)解:22+12(3)2(3), 4+(12+6)(3),4+18(3),4+(6),10(3)解:( 56 )|1 23 |+(2)3(1.5), ( 56 ) 35 +(8)(1.5), 12 +12,11 12