搜狗做题网(8-x) (20-x)=1 3
来源：学生作业帮助网 编辑：作业帮 时间：2024/07/31 01:48:10
设X²+3X为Y;Y-8=20/Y;Y²-8Y-20=0;(Y-10)(Y+2)=0;Y=10或-2;所以：1：X²+3X=10,X=2或-5;2:X²+3X=
5*(x-2)=4*(x+3)5x-10=4x+125x-4x=12+10x=222x+（50-x）*4=1402x+200-4x=1404x-2x=200-1402x=60x=60÷2x=303x-
1、56-8X=11+X8X+X=56-119X=45X=52、3X-2=X+1+6X3X-2=7X+17X-3X=-2-14X=-3X=-3/43、7+X=2X+20-14X7+X=20-12XX+
1x+2x+3x+4x+5x+6x+7x+8x+9x+10x+11x+12x+13x+14x+15x=550120x=550x=55/12=4.583
x(1+2+...+9)=x(9-8-7-...-1)x=0记得采纳啊
原式=x^4-8x^3+13x^2+10+2x(x^2-8x+13)+(x^2-8x+13)=x^2(x^2-8x+13)+10=10分组代入后得10
8x+4(10-x)=20,8x+40-4x=20,4x=-20,x=-5
1/4X=13X=5210/3X=20/21X=2/70.72X=12.96X=18
设x1=4-√3,x2=4+√3,是方程X^2-8X+13=0的两根所以X1^2-8X1+15=2X^4-6X^3-2X^2+18X+23=(X+1)^2*(X^2-8X+13)+10=10所以原式=
60X+15X+10X+6X=12091X=120X=120/91
(x-22)+(x-24)+(x-27)+(x-20)=xx-22+x-24+x-27+x-20=x4x-93=x4x-x=933x=93x=31
1.[-5/2,-2)2.M0可解得X>4或X=0可解得X>=-5/2或X
x+17=3(x+13),x+17=3x+39x-3x=39-17-2x=22x=22/-2x=-112x-11.2=0.6x,2x-0.6x=11.21.4x=11.2x=11.2/1.4x=82.
各分式减1,得1/（x+2004)+1/(x+2006)=1/(x+2007)+1/(x+2003),通分得（2x+4010)/[（x+2004)(x+2006)]=(2x+4010)/[(x+200
=x^2+10x-24+x^2+15x+56-x^2+5x+50=x^2+30x+82=4+60+82=146其实,不化简,直接代入=14*0+9*10+7*8=0+90+56=146也很简单
2x+0.4x=48(2+0.4)x=48x=48/2.4x=20(并检验)2×20+0.4×20=40+8=488x-x=14.7(8-1)x=14.7x=14.7/7x=2.135x+13x=9.
再问：看不清耶再答：我重拍再问：我采纳再答： 再答：不是说采纳的么再答：棒
(20-2x)(8-x)=126(10-x)(8-x)=63x²-18x+80-63=0x²-18x+17=0(x-1)(x-17)=0x=1,x=17
8(5+x)=13x40+8x=13x13x-8x=405x=40x=8再问：20x+12x=22413x+15x=33699x-72x=5443x+22x+22x=65*313x=8x+15015x
各项乘以120得3x+2x+3[20-(x/40+x/60)*8]=3x+15(20-x)2x+60-24(x/40+x/60)=15(20-x)2x+60-0.6x-0.4x=300-15xx+15