|x-2|+(y+1)的平方=0
则x-2=0 y+1=0
x=2 y= -1
则0.5x-3(2x-2/3y的平方)+(-3/2x+y的平方)
=0.5×2-3×【2×2-2/3×（-1）²】+【-3/2×2+（-1）²】
=1-3×【4-2/3】+【-3+1】
=1-10-2
= -11