If $x-frac{1}{x}=5$, then $x^{2}+frac{1}{x^{2}}$ is :

$x-frac{1}{x}=5$

On squaring both sides, $x^{2}+frac{1}{x^{2}}-2=25$

$Rightarrow x^{2}+frac{1}{x^{2}}=27$