## College Algebra 7th Edition

$9(x-5)(x+1)$
First, factor out the greatest common factor, which is $9$. $9x^{2}-36x-45=9(x^{2}-4x-5)$ Then, use FOIL to factor the trinomial. $9(x^{2}-4x-5)=9(x-5)(x+1)$