Answer
The factor of the given polynomial is $(y-8)(y+5)$.
Work Step by Step
The given polynomial is
$=y^2-3y-40$
Rewrite $-3y$ as $-8y+5y$.
$=y^2-8y+5y-40$
Group the terms.
$=(y^2-8y)+(5y-40)$
Factor each group.
$=y(y-8)+5(y-8)$
Factor out $(y-8)$.
$=(y-8)(y+5)$
Hence, the factor of the given polynomial is $(y-8)(y+5)$.
