Answer
$|y|$
Work Step by Step
Using $\sqrt{x^2}=|x|$, the given expression, $
\sqrt[8]{y^8}
,$ simplifies to
\begin{array}{l}
\sqrt[8]{(y)^8}
\\\\=
|y|
.\end{array}
We put the variable in absolute value bars since it is being raised to an odd power.