## Precalculus (6th Edition) Blitzer

$e$
The given trinomial can be written as $(3x)^2+2(3x)(4)+(4)^2.$ The trinomial above is a perfect square trinomial of the form $a^2+2ab+b^2$ where $a=3x$ and $b=4$. Thus, the given trinomial can be factored using technique (e).