Question

Question was provided via image upload.

Explanation:

Step1: Factor out perfect square

$\sqrt{20} = \sqrt{4 \times 5}$

Step2: Split the radical

$\sqrt{4 \times 5} = \sqrt{4} \times \sqrt{5}$

Step3: Simplify perfect square root

$\sqrt{4} \times \sqrt{5} = 2\sqrt{5}$

Answer:

$2\sqrt{5}$