\(3x^2y-4xy^2=xy\left(3x-4y\right)\)
\(\left(x-2\right)^2-y^2=\left(x-y-2\right)\left(x+y-2\right)\)
\(x^2+xy+xz+yz=x\left(x+y\right)+z\left(x+y\right)=\left(x+z\right)\left(x+y\right)\)
\(x^2+4xy-5y^2=x^2-xy+5xy-5y^2=x\left(x-y\right)+5y\left(x-y\right)=\left(x-y\right)\left(x+5y\right)\)
a)
3x2y - 4xy2
= xy.(3x - 4y)
b)
(x - 2)2-y2
=(x - 2 -y) (x - 2 + y)
c)
x2 + xy + xz + yz
= (x2+xy) + (xz + yz)
= x (x + y) + z (x + y)
= (x + y)(x + z)
d)
x2 + 4xy - 5y2
= x2 - xy + 5xy - 5y2
= x(x + y) + 5y(x - y)
= (x - y)(x + 5y
a: \(=xy\left(3x-4y\right)\)
b: \(=\left(x-2-y\right)\left(x-2+y\right)\)
c: \(=x\left(x+y\right)+z\left(x+y\right)=\left(x+y\right)\left(x+z\right)\)
d: \(=x^2+5xy-xy-5y^2=\left(x+5y\right)\left(x-y\right)\)


