2-（1-y)=-2
2+2=1-y
4=1-y
y=1-4
y=-33-2（x+1）=2（x-3）3-2（x+1)=2(x-3)3-(2x+2）=2x-63-2x-2=2x-63-2+6=2x+2x4x=7x=7/4