(1)m^2-4m+4(2)x^2+4x+4y^2（3）4x^2+2xy+1/4y^2（4）x^2-xy+y^2（5）x^2-6x-9

Question

(6)-x^2+x-0.25

Answer 1

x²+y²
=(x+y)²-2xy
=(-5)²-2×3
=25-6
=19