# What is the square root of 5 plus the square root of 20?

Sep 10, 2015

= color(blue)(3sqrt5

#### Explanation:

Simplifying $\sqrt{20}$ by prime factorisation:

sqrt20 = sqrt(2^2 *5)=color(blue)(2sqrt5

The expression can now be written as
sqrt 5 +sqrt20 = sqrt5 +color(blue)(2sqrt5

 sqrt5 +2sqrt5 = color(blue)(3sqrt5