Question

Give the final factored form of the expression. Provide an explanation AND identify the type of factoring used.

x2 – 9y2
You don't have to identify the type of factoring used, but I need help with the rest, please and thank you.

Answer 1

$(x^2-9y^2)=\\ (x^2-(3y)^2)=\\ (x-3y)(x+3y)\\\\ (a^2-b^2)=(a-b)(a+b)$