Answer
{$-4,4$}
Work Step by Step
Simplifying the expression through division and then applying square root on both sides, we obtain:
$4x^{2}=64$
$x^{2}=\frac{64}{4}$
$x^{2}=16$
$\sqrt {x^{2}}=\pm\sqrt {16}$
$\sqrt {x^{2}}=\pm\sqrt {4^{2}}$
$x=\pm 4$
Therefore, the solution set is {$-4,4$}.
