解方程：7x+2x=0.81;4(x-6)=36;2x+0.2xX2=36

解方程：7x+2x=0.81;4(x-6)=36;2x+0.2xX2=36 2x+0.2xX2=36用方程怎么解 7x+2x=0.81 4(x-6)=36 2x+0.2xX2=36 3.4x-6=4.2 7.8x+5=44 7.5x+ 已知x+1x=2，那么xx2+3x+1-xx2+9x+1的值等于 ___ ． 解方程2xx2-1-3x2-3x=2时，若设y=xx2-1，则方程可化为 ___ ． Xx2.25%x（1-20%）+x=81440, 解方程(x-2)/(x-3)-(x-3)/(x-4)=(x-5)/(x-6)-(x-6)/(x-7) 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+1+x+8/x+7=x+6/x+5+x+4/x+3 解方程 7x+2x=0.81 4(x-6)=36 2x+0.2X2=36 解方程：7x-2x+3x=36 解方程7x-2x+3x=36