Question

Factor 9x^2 - 16

Answer 1

Any ideas?

Answer 2

I know your supposed to find the the square roots. So the spuare root of 9 would be 3, and the square root of 16 would be 4 right?

Answer 3

$$\Huge 9x^2-16=(3x)^2-4^2$$

Answer 4

\[9x^2- 16 = (3x)^2-(4)^2 = (3x+4) (3x-4) \]

are the required factors

Answer 5

6x^2-16?

Answer 6

nope

Answer 7

How would I solve (3x)^2-4^2?

Answer 8

Have you seen the formula for the difference of two squares?

Answer 9

a^2-b^2= (a+b)(a-b)

Answer 10

$$\Huge a^2-b^2=(a+b)(a-b)$$

Answer 11

a = 3x and b = 4

Answer 12

3x^2 - 4^2= (3x + 4)(3x-4)?

Answer 13

So that's my answer or do I need to simplify it more?

Answer 14

9x^2 - 16 = (3x)^2 - 4^2

Answer 15

Oh, I see what to do now. Thank you @skullpatrol

Answer 16

Thanks for learning some new math :)