Answer
$5$, then $6\sqrt3$
Work Step by Step
$\sqrt3 + \sqrt {75}$
Split 75 into two factors such that one is a perfect square:
$=\sqrt3 + \sqrt {25\cdot3}$
(not shown: $=\sqrt3 + \sqrt {25}\sqrt3$)
$=\sqrt3 + 5\sqrt3$
(not shown: $=1\sqrt3 +5\sqrt3 = (1+5)\sqrt3$)
$=6\sqrt3$
