#### Answer

$3\sqrt{5}$

#### Work Step by Step

Simplify the radicals that can still be simplified by factoring the radicand so that one of the factors is a perfect square:
$=\sqrt5+\sqrt{4(5)}
\\=\sqrt5 + \sqrt{2^2(5)}
\\=\sqrt5 + 2 \sqrt5$
RECALL:
For any real numbers $a, b,$ and $c$,
$ac+bc=(a+b)c$
Use the rule above to combine like terms:
$=(1+2)\sqrt{5}
\\=3\sqrt{5}$