(3b-2)²+/2a-b-3/=0,
3b-2=0
b=2/3
2a-b-3=0
2a=b+3=2/3+3=11/3
a=11/6
5(2a-b)-2(6a-2b+1)+（4a-3b-1/2)
=10a-5b-12a+4b-2+4a-3b-1/2
=2a-4b-5/2
=11/6x2-2/3x4-5/2
=11/3-8/3-5/2
=1-5/2
=-3/2