解方程.4(5x-2.5)+2x=12

解方程 x(2x-4)+3x(x-1)=5x(x-3)+8 解方程3x=x+4,2.6x-8=2.4x,4x+12=10x+3 ,7x=12-×,2.5x=2x+4,5x+3=6x 解方程:x^4+2x^3+5x^2+4x-12=0 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：2x+4x+6x...+100x=1-(x+3x+5x+...+99x) 解方程 x+2/x+1+x+8/x+7=x+6/x+5+x+4/x+3 5x+2x=33.6,7x-4x=0.75,2x+7x+2.1=12,56x-32x-119=361,解方程 解方程1/(x+x﹚+1/(x+3x+2﹚+1/(x+5x+6﹚+1/(x+7x+12﹚=4/21得 解方程5/(x^-2x)-4/(x^2+2x)=3/x^2-4 解分式方程：4/5x+x/(5x-25)=5/(x^2-5x) 解方程:x/2+x/6+x/12+x/20+x/30=5