12.6-3x=2.1

12.6-3x=2.1 3x一1.5X+0.3x=12.6 1.(x*2-3x+3)/(x*2-3x+2)-(x*2-5x+7)/(x*2-5x+6)-1/(x*2-4x+3)2.1/x(x+1)+2/(x+1)(x+3)+3/(x+3)(x+6) 3.已知：x*2-3x+1=0,求x*2+1/x*2. 用递归法求y=x-(x*x*x/3!)+(x*x*x*x*x/5!)-(x*x*x*x*x*x*x/7!)+. 0.6+3X=2.1-2X （16）3（x-2.1）=8.4（17）5.06x+0.94x=1.8(18)(2x+3)/0.5=10(19)5x+24*1.5=66(20)7.2x-3.8x-7.8=12.6 (1) 2.5+3X=1.1 (2) 12X-5X=2.1 (3) X-0.3X=1.4 X=1.1 X=2.1 X=1.4 X=?X=0.3 X=? 9x-0.9乘7=2x+2.1 x=?9x-0.9乘7=2x+2.1 x=?还有：3(2x-1.2)=2(x+3.5) x=?2.4x-9.8=1.4x-9 4.2-0.6x=3.6x 5x+2x=33.6 7x-4x=0.75 2x+7x+2.1=12 56x-32x-119=361 x+5=2x 3x+9=6x 4x-28=2x 2x+18=7x 5x=25*4-15x 7x-x+2*3=29.4 (28.8+5.5x+3.2）除2=71 1.解方程：2x-1分之x-1 + 1-2x分之5x-8= - 3 2.1-x分之3-x - 7-x分之5-x =1 - x²-8x+7分之x²-2 0.6+3x+2.1-2x解方程0.6+3X=2.1-2X 3x*x=1600+x*x-80x (X+1)X(X+2)X(X+3)=504 0.3+0.3x=0.39 x= 2x-1.5x=7.6x x= 0.36x÷0.3=1.2 x=6（x+1.2)=18.6 x= 7x+2x = 8.1 x= (x-5）÷3=1.7 x=5（x+1.1)=15.5 x= 9x+25=70 x= 7x-4x=2.1 x= 一个“整式的乘法”的问题请先阅读下列解题过程,再仿做下面的问题.已知X*X + X - 1=0,求X*X*X + 2*X*X + 3的值.解X*X*X + 2X*X +3=X*X*X +X*X -X +X*X +X +3=X{X*X +X -1} +X*X +X -1 +4=0+0+4=4+ x + X*X + X*X*X=0.+ X*X + X*X*X 2x+3x=10 2.1x+1.4=35 7x减1.4x=1.28 明天早上就交,2x+3x=10 2.1x+1.4=35 7x减1.4x=1.28 x+2x+3x+4x+5x+6x+7x+8x+9x=9x-8x-7x-6x-5x-4x-3x-2x-x.x等于多少? 12x-9x=8.7 6x+18=48 3（x+2.1)=10.5 x+4.8=7.2