Answer
$\dfrac{\sqrt{10}}{2}$
Work Step by Step
Rationalize the denominator by multiplying $\sqrt{10}$ to both the numerator and the denominator to have:
$=\dfrac{5}{\sqrt{10}} \cdot \dfrac{\sqrt{10}}{\sqrt{10}}
\\=\dfrac{5\sqrt{10}}{10}$
Cancel the common factor $5$ to have:
$=\dfrac{\sqrt{10}}{2}$
