Answer
$\color{blue}{\bf{ 16k^2 - 6k - 8 }}$
Work Step by Step
We are given the two functions $\bf{f}$ and $\bf{g}$
$\bf{f(x) = 3x^2 - 4 }$ and $\bf{g(x) = x^2 - 3x - 4 }$
We are asked to find $\bf{ ( f+g )(2k) }$
$( f+g )(2k) = 3(2k)^2 - 4+ (2k)^2 - 3(2k)- 4 $
$ 3(4)k^2 - 4+ 4k^2 - 6k - 4 $
$ 16k^2 - 6k - 8 $
$\color{blue}{\bf{ 16k^2 - 6k - 8 }}$
