（2x-4)*0.7+4=2*0.8x(x是未知数,“*”是乘号）

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 *-----------------------------------------------*| 6 4 X | 8 X X | X X 5 || X X X | X X X | X 7 8 || X X X | X X X | X X X ||---------------+---------------+--------------- || X X X | X X X | 5 1 X || X X X | X 6 X | X X X || 8 X X | 3 5 X | 2 X X || x+2x+3x+4x+5x+6x+7x+8x+9x=9x-8x-7x-6x-5x-4x-3x-2x-x.x等于多少? (x/x-2)+(2/x*2+2x)-(x+6/x*2-4)化简,=x^2/x(x-2)+(2x-4)/x(x^2-4)-(x^2+6x)/x(x^2-4)=x^2/x(x-2)-(x+2)/x(x-2)=(x-2)(x+1)/x(x-2)=(x+1)/x 先化简,再求值：（x-2/x-x+2/x)/x-2/4x,x=2011 (x-3/x-2)-(x-2/x-1)=(x-5/x4) -(x-4/x-3) 0.8*50x>0.7*50(x+4) 0.8*50x=0.7*50(x+4) 0.8*50x(1)0.8*50x>0.7*50(x+4)(2)0.8*50x=0.7*50(x+4)(3)0.8*50x x-2x+3x-4x+5x.+99x-100x=25求解 2x+3x+4x+5x+x+6x+7x=100 x(x+1)+(x+2)+(x+3)+(x+4)+(x+5) = 27求x (x/x-2-x/x+2)/4x/x-2 X+X+X+(X-1)+(X-2)+(X-3)+(X-4)=10(X-3)+(X-4) 解方程(x/x(x+2))+(x/(x+2)(x+4))+.+x/(x+8)(x+10)=1 x+2/x+1-x+4/x+3=x+6/x+5-x+8/x+7 x=? x^4+x^3+x^2+x+1=0,x^2006+x^2005+x^2004+x^2003+x^2002 x-x/4-120=x/2 x^2-3x=x-4 x(x-4)=2-8x