Question

Completely factor 9x^2-36a^4

Answer 1

note that 9x^2 and 36a^4 are perfect squares
- we have the difference of 2 squares so we use the identity

a^2 - b^2 = (a + b)(a - b)
where a = 3x and b = 6a^2

Answer 2

What's next?

Answer 3

thats
(3x + 6a^2)(3x - 6a^2)
now we can take out 3
= 3(x + 2a^2)* 3(x - 2a^2)
= 9(x + 2a^2)(x - 2a^2)

Answer 4

Thanks! Can you help me with a couple more?