Question

What is (81x^2 -4y^2) square units factored?

Answer 1

To solve, use the difference of squares rule. (a^2-b^2)=(a-b)(a+b). In your equation, your a^2=81x^2 and your b^2=4y^2, making your a=9x and your b=2y. This makes your factored form (9x-2y)(9x+2y).