How do you factor 81p^2 - 144y^2?

1 Answer
Sep 27, 2016

(9p+12y)(9p-12y)

Explanation:

If you look carefully at the two terms in the polynomial, you'll quickly figure out that they are square numbers.

Thus, you can write them like this:

81p^2-144y^2 is the same as (9p)^2-(12y)^2

This actually looks like a^2-b^2, where a=9p and b=12y

Recall the identity, a^2-b^2=(a+b)(a-b)

Now you just have to put it in that form!

(9p)^2-(12y)^2=(9p+12y)(9p-12y)