#### Answer

$15\sqrt{3}$

#### Work Step by Step

Simplify each radical to obtain:
$=5\sqrt{4(3)} +\sqrt{25(3)}
\\=5\sqrt{2^2(3)} +\sqrt{5^2(3)}
\\=5(2)\sqrt{3}+5\sqrt{3}
\\=10\sqrt{3} + 5\sqrt{3}$
RECALL:
The distributive property states that for any real numbers a, b, and c:
(1) $ac + bc = (a+b)c$
(2) $ac-bc=(a-b)c$
Use rule (1) above to combine like terms and obtain:
$=(10+5)\sqrt{3}
\\=15\sqrt{3}$