Answer
$\frac{\sqrt {10y}}{5y}$
Work Step by Step
First, we need to cancel out common terms in the numerator and denominator:
$\sqrt {\frac{2}{5y}}$
Separate the radical:
$\frac{\sqrt {2}}{\sqrt {5y}}$
We don't want to leave radicals in the denominator, so to get rid of radicals in the denominator, we multiply both the numerator and denominator by the denominator:
$\frac{\sqrt {2}}{\sqrt {5y}} • \frac{\sqrt {5y}}{\sqrt {5y}}$
Multiply to simplify:
$\frac{\sqrt {10y}}{\sqrt {25y^2}}$
Take the square root of any perfect squares:
$\frac{\sqrt {10y}}{5y}$