1.3/4x-0.4=1/2x+0.3
3/4x-1/2x=0.3+0.4
1/4x=0.7
x=0.7*4=2.8
2.2x1/2(x-1)=2/3(x+2)
x-1=2/3(x+2)
x-1=2/3x+4/3
-1/3x=7/3
x=-7
3.x-2x+1/2=9-8-x/4
-x+1/2=1-1/4x
3/4x=-1/2
x=-2/3
4.2/3[3/2-(1/4x-1)-4又1/2]=x+2
2/3(-2-1/4x)=x+2
-4/3-1/6x=x+2
7/6x=-10/3
x=-20/7