Math help?

Question

How do you factor:

x² - 36y²

Do you used the greatest common factor method? If so, how and what is the final answer? What is the GCF?

Answer 1

x squared minus 36 y squared, factors as follows:

(x-6y) (x +6y) is the answer, arrived at as follows:

when you cross multiply, you get:

x squared minus 6xy plus 6 xy -36y squared

the 6xy's--minus and plus--cancel out to zero

Answer 2

I don't know how to factor that expression, but I use the factor tree to find the greatest common factor.