# What is the square root for 40.5?

Aug 6, 2018

$\frac{9 \sqrt{2}}{2}$

#### Explanation:

$40.5 = \frac{81}{2}$

$\sqrt{40.5} = \sqrt{\frac{81}{2}} = \frac{9}{\sqrt{2}}$

Rationalise the denominator by multiplying numerator and denominator by $\sqrt{2}$

$\frac{9}{\sqrt{2}} = \frac{9 \sqrt{2}}{2}$