Hello, madelynnnnnn!

Simplify the expressions.

\(\displaystyle \L 1)\;\sqrt{\frac{5}{12}}\)

then i think you go... \(\displaystyle \L\frac{\sqrt{5}}{2\sqrt{3}}\)

This is correct, but you're probably expected to rationalize the denominator.

\(\displaystyle \L\;\;\frac{5}{2\sqrt{3}}\cdot\frac{\sqrt{3}}{\sqrt{3}}\;=\;\frac{5\sqrt{3}}{6}\)

\(\displaystyle \L2)\; \sqrt{\frac{3}{7}}\;\) and in that one i dont see any perfect squares

No, but we have:

.\(\displaystyle \L\,\frac{\sqrt{3}}{\sqrt{7}}\) . . . which we must rationalize.

\(\displaystyle \L\;\;\frac{\sqrt{3}}{\sqrt{7}}\cdot\frac{\sqrt{7}}{\sqrt{7}}\;=\;\frac{\sqrt{21}}{7}\)

\(\displaystyle \L3)\;\sqrt{\frac{10}{3}}\,\cdot\,\sqrt{\frac{9}{5}}\)

These can be combined: \(\displaystyle \L\,\sqrt{\frac{10}{3}\cdot\frac{9}{5}} \;=\;\sqrt{6}\)