## Calculus with Applications (10th Edition)

$6(a-10)(a+2)$
Factor out $6$ to have: $=6(a^2 -8a-20)$ The leading coefficient of the trinomial factor is 1. To factor the trinomial, just look for the factors of the constant term (-20) whose sum is equal to the coefficient of the middle term (-8). These factors are $-10$ and $2$. Thus, the completely factored form of the given expression is: $=6(a-10)(a+2)$