Chapter 6 - Section 6.2 - Factoring Trinomials Whose Leading Coefficient is 1 - Exercise Set - Page 436: 75

$2x^{2}(y-15z)(y-z)$

First, there is a GCF (of all terms), GCF=$2x^{2}$ $...=2x^{2}(y^{2}-16yz+15z^{2})$ We want to factor the parentheses in form $(y +....)(y+....)$. Searching for two factors of $15z^{2}$ such that their sum is $-16z...$ we find $-15z$ and $-z.$ = $2x^{2}(y-15z)(y-z)$ All are prime, factorization is complete.