Answer
$\left\{-2, 2\right\}$
Work Step by Step
Add 16 on both sides of the equation to obtain:
$x^4=16$
Write $16$ as $2^4$ to obtain:
$x^4=(2)^4$
Take the fourth root of both sides to obtain:
$x = \pm \sqrt[4]{2^4}
\\x = \pm 22$
Thus, the solution set of the given equation is $\left\{-2, 2\right\}$.
