若a.b为实数.且a²+|4b+3|=4a-4,求|ab|的值

a²+|4b+3|=4a-4
a²-4a+4+|4b+3|=0
(a-2)²+|4b+3|=0
a-2=0,a=2
4b+3=0,b=-3/4
IabI
=I2x(-3/4)I
=3/2
不懂的欢迎追问.