已知4x²+y²-4x+6y+10=0,求4x²-12xy+9y²的值

4x²+y²-4x+6y+10=0
(2x-1)²+(y+3)²=0
2x-1=0
y+3=0
x=0.5
y=-3
4x²-12xy+9y²
=(2x-3y)²
=(1+9)²
=100