Question 116511
Rewrite the middle term as the sum of two terms and then factor completely.
4{{{z^3}}}-18{{{z^2}}}-10z
I think I'm thinking too hard
___________

Um, I think you are, too  ;)

Seriously though, a better approach is to start by factoring out a 2z:

(2z)(2{{{z^2}}}-9z-5)

Then, factor the remaining polynomial.  We're looking for factors of -5 that total -9 after multiplying one of the factors by 2...and it so happens that -5 and 1 work if they are placed thusly:

(2z)(2z+1)(z-5) (answer)