#### Answer

{$-1,1$}

#### Work Step by Step

First we isolate the unknown variable,
$5n^{2}-5=0$
$5n^{2}=5$
$n^{2}=\frac{5}{5}$
$n^{2}=1$
Next, we apply square root to both sides of the equation and solve:
$\sqrt {n^{2}}=\pm\sqrt 1$
$n=\pm\sqrt 1$
$n=\pm 1$
Therefore, the solution set is {$-1,1$}.