Answer
$10|x|$
Work Step by Step
Using $\sqrt{x^2}=|x|$, the given expression, $
\sqrt{100x^2}
,$ simplifies to
\begin{array}{l}
\sqrt{(10x)^2}
\\\\=
|10x|
\\\\=
10|x|
.\end{array}
Note: We have to put the variable in absolute value bars since it is being raised to an odd power.