what do you do when you have a number on the outside of a cubes root or squared root?

Remember that      $\sqrt[a]{b}\,=\,b^{\frac1a}$    .

Here's some examples:

$\sqrt[3]8=8^{\frac13}=2 \\~\\ \sqrt[2]{25}=25^{\frac12}=5 \\~\\ \sqrt[2]{45^2}=(45^2)^{\frac12}=45^\frac22=45^1=45$

If that doesn't help you solve your problem feel free to post it on here.