4x+(x+31)*7+(85-(x+31) -x)*2=500 怎么解

7x(x-6)+3x=4x(2x+5)怎么解这个方程 解方程:(x+3)/(x+2)-(x+5)/(x+4)=(x+7)/(x+6)-(x+9)/(x+8) 解方程(x-2)/(x-3)-(x-3)/(x-4)=(x-5)/(x-6)-(x-6)/(x-7) 解方程】(x+8)/(x-3)-(x-9)/(x-4)=(x+7)/(x+8)-(x+2)/(x+3) 解方程：（x-8）/(x-3)-(x-9)/(x-4)=(x+7)/(x+8)-(x+2)/(x+3) 解方程 x+2/x+1+x+8/x+7=x+6/x+5+x+4/x+3 x-2x-7x=4x-56怎么解 3x-2x(x-1)=4*1.5-7x 怎么解方程式 1/2x+1\4x+1/7x=x-3怎么解这个方程? 解方程(x²-x+4)x-(x-1)(x²+2)=x+7 x^2=(x+30)X(x-18)怎么解 x+2x+3x+4x+5x+6x+7x+8x+9x=9x-8x-7x-6x-5x-4x-3x-2x-x.x等于多少?