1.2(x-4)=12
2x-8=12
2x=12+8
2x=20
x=10
2.5(x-1)-2(1-x)=3+2x
5x-5-2+2x=3+2x
7x-2x=3+2+5
5x=10
x=2
3.2(3x+4)-5(x+1)=3
6x+8-5x-5=3
x=3-3
x=0