# How do you find the square root of -63?

Jun 5, 2018

$3 i \sqrt{7}$

#### Explanation:

$\sqrt{- 63}$

first of all this is an imaginary number so we do this $\sqrt{- 1} = i$:

$= \sqrt{63} \cdot \sqrt{- 1}$

$= \sqrt{63} \cdot i$

$= \sqrt{3 \cdot 3 \cdot 7} \cdot i$

$= \sqrt{{3}^{2} \cdot 7} \cdot i$

$= 3 \sqrt{7} \cdot i$

$= 3 i \sqrt{7}$