Evaluate square root of -900

$\sqrt{- 900}$

Step 1

Rewrite $- 900$ as $- 1 (900)$ .

$\sqrt{- 1 (900)}$

Step 2

Rewrite $\sqrt{- 1 (900)}$ as $\sqrt{- 1} \cdot \sqrt{900}$ .

$\sqrt{- 1} \cdot \sqrt{900}$

Step 3

Rewrite $\sqrt{- 1}$ as $i$ .

$i \cdot \sqrt{900}$

Step 4

Rewrite $900$ as $30^{2}$ .

$i \cdot \sqrt{30^{2}}$

Step 5

Pull terms out from under the radical, assuming positive real numbers.

$i \cdot 30$

Step 6

Move $30$ to the left of $i$ .

$30 i$