Factor ax^2-16a

$a x^{2} - 16 a$

Step 1

Factor $a$ out of $a x^{2} - 16 a$ .

Factor $a$ out of $a x^{2}$ .

$a (x^{2}) - 16 a$

Factor $a$ out of $- 16 a$ .

$a (x^{2}) + a \cdot - 16$

Factor $a$ out of $a (x^{2}) + a \cdot - 16$ .

$a (x^{2} - 16)$

Step 2

Rewrite $16$ as $4^{2}$ .

$a (x^{2} - 4^{2})$

Step 3

Factor.

Since both terms are perfect squares, factor using the difference of squares formula, $a^{2} - b^{2} = (a + b) (a - b)$ where $a = x$ and $b = 4$ .

$a ((x + 4) (x - 4))$

Remove unnecessary parentheses.

$a (x + 4) (x - 4)$