Pre-Algebra Examples

$16 x^{4} - 121$

Step 1

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

${(4 x^{2})}^{2} - 121$

Step 2

Rewrite $121$ as $11^{2}$ .

${(4 x^{2})}^{2} - 11^{2}$

Step 3

Since both terms are perfect squares, factor using the difference of squares formula, $a^{2} - b^{2} = (a + b) (a - b)$ where $a = 4 x^{2}$ and $b = 11$ .

$(4 x^{2} + 11) (4 x^{2} - 11)$