Question

How do you factor x³-9?

Answer 1

Answer:

(x² + 3)(x-3)

Step-by-step explanation:

Since the exponent is uneven you can take 2 and 1 and add them to the x's multiply to get 3 and since 9 is a perfect square you can square root it and get 3 which you put on both sides. Since the 9 is negative one of the symbols have to be negative, usually put in the second parenthesis.

Hope this helps!

Answer 2

Remember SOAP. Same, opposite, always positive.
(X-3)(x^2+3x+9)
The formula is (a+b)(a^2+ab+b^2) but the pluses and minuses follow SOAP