3-(4x-3)=7
3-4x+3=7
6-4x=7
4x=6-7
4x=-1
x=-1/4
3-2x=1-3x
3x-2x=1-3
x=-2
3-x/2=4x
4x+x/2=3
9x/2=3
9x=6
x=6/9
x=2/3