simplify.\n$sqrt{20}$

Explanation:

Step1: Factorize the number inside square - root

We know that $20 = 4\times5$. So, $\sqrt{20}=\sqrt{4\times5}$.

Step2: Use the square - root property $\sqrt{ab}=\sqrt{a}\cdot\sqrt{b}$ ($a = 4$, $b = 5$)

$\sqrt{4\times5}=\sqrt{4}\cdot\sqrt{5}$.

Step3: Calculate $\sqrt{4}$

Since $2\times2 = 4$, $\sqrt{4}=2$. So, $\sqrt{4}\cdot\sqrt{5}=2\sqrt{5}$.

Answer:

$2\sqrt{5}$