## Intermediate Algebra (6th Edition)

$-16(y+2)(y-2)$
Factoring the negative $GCF= -16$ results to $-16(y^2-4)$. Using $a^2-b^2=(a+b)(a-b)$ or the factoring of the difference of 2 squares, then, \begin{array}{l} -16(y^2-4) \\= -16(y+2)(y-2) .\end{array}