Answer
$2(6-y)(6+y)$
Work Step by Step
RECALL:
A difference of two squares can be factored using the formula:
$a^2-b^2=(a-b)(a+b)$
Factor out the greatest common factor, $2$, to obtain:
$=2(36-y^2)
\\=2(6^2-y^2)$
The binomial is a difference of two squares.
Factor the given difference of two squares using the formula above with $a=6$ and $b=y$ to obtain:
$=2(6-y)(6+y)$