# How do you simplify 2sqrt(125x)?

$2 \sqrt{125 x} = 2 \sqrt{{5}^{2} \cdot 5 x} = 2 \sqrt{{5}^{2}} \sqrt{5 x} = 2 \cdot 5 \sqrt{5 x} = 10 \sqrt{5 x}$
using $\sqrt{a b} = \sqrt{a} \cdot \sqrt{b}$