Answer
$3(5y^2-y+3)$
Work Step by Step
Factoring the $GCF=
3
,$ the given expression, $
15y^2-3y+9
,$ is equivalent to
\begin{array}{l}\require{cancel}
3
\left(
\dfrac{15y^2}{3}-\dfrac{3y}{3}+\dfrac{9}{3}
\right)
\\\\=
3(5y^2-y+3)
.\end{array}