Question

Answer 1

a: \(5a\left(x-y\right)+7\left(x-y\right)=\left(x-y\right)\left(5a+7\right)\)

b: \(5x-15+3xy-9y=\left(x-3\right)\left(5+3y\right)\)

c: \(x^2-10x+25-81y^2=\left(x-5-9y\right)\left(x-5+9y\right)\)