|x+1|+（y+2分之1）的平方=0
x+1=0
y+2分之1=0
x=-1
y=-2分之1

3X-2y-[-4x+(y+3x)]-(2x-3y)
=3X-2y-(-4x+y+3x)-2x+3y
=3X-2y+4x-y-3x-2x+3y
=(3+4-3-2)x+(-2-1+3)y
=2x
=2*(-1)
=-2