Question

Simplify: (3x + 12) (3x - 12).

Answer 1

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

Here, a = 3x and b = 12

If you can compute (3x)^2 and (12)^2 , you will be able to get the rest of this answer.

Answer 2

so 3x^2 - 12^2 ?

Answer 3

One more hint:

(cd)^2 = (c^2)(d^2)

So, you have to square the "3" and the "x".

Answer 4

im so confused

Answer 5

What is 3^2?

Answer 6

3x squared

Answer 7

3 squared i mean

Answer 8

9

Answer 9

3*3 is 9 i mean

Answer 10

so 9x^2 then what

Answer 11

3^2 is "3 squared". That means: 3 times 3. That is 9, so:

(3x)^2 = 9x^2 not 3x^2

Also 12^2 = 144

So,

9x^2 - 144

Answer 12

So, (3x + 12)(3x - 12) = 9x^2 - 144

Answer 13

This is because::

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