1. x2 - 4x + 4 - x2y + 2xy
= (x - 2)2 - xy(x - 2)
= (x - 2 - xy)(x - 2)
2. x2 + 4x - 5
= x2 - x + 5x - 5
= x(x - 1) + 5(x - 1)
= (x + 5)(x - 1)
3. x2 + 7x + 12
= x2 + 3x + 4x + 12
= x(x + 3) + 4(x + 3)
= (x + 4)(x + 3)
1) \(x^2-4x+4-x^2y+2xy=\left(x-2\right)^2-xy\left(x-2\right)=\left(x-2\right)\left(x-2-xy\right)\)
2) \(x^2+4x-5=x\left(x-1\right)+5\left(x-1\right)=\left(x-1\right)\left(x+5\right)\)
3) \(x^2+7x+12=x\left(x+3\right)+4\left(x+3\right)=\left(x+3\right)\left(x+4\right)\)
b: \(x^2+4x-5=\left(x+5\right)\left(x-1\right)\)
c: \(x^2+7x+12=\left(x+3\right)\left(x+4\right)\)