Factor 16a^2-49

$16 a^{2} - 49$

Step 1

Rewrite $16 a^{2}$ as ${(4 a)}^{2}$ .

${(4 a)}^{2} - 49$

Step 2

Rewrite $49$ as $7^{2}$ .

${(4 a)}^{2} - 7^{2}$

Step 3

Since both terms are perfect squares, factor using the difference of squares formula, $a^{2} - b^{2} = (a + b) (a - b)$ where $a = 4 a$ and $b = 7$ .

$(4 a + 7) (4 a - 7)$