Answer
$-8(x^4-4x^3-2x^2)$
Work Step by Step
Factoring the negative $GCF=
-8
,$ the given expression, $
-8x^4+32x^3+16x^2
,$ is equivalent to
\begin{array}{l}\require{cancel}
-8
\left(
\dfrac{-8x^4}{-8}+\dfrac{32x^3}{-8}+\dfrac{16x^2}{-8}
\right)
\\\\=
-8(x^4-4x^3-2x^2)
.\end{array}