Answer
$g(x) =5 -3\frac{1}{2}x$
Work Step by Step
$f(x) = 3x + 1 $
$ (f + g) (x) = 6 - \frac{1}{2}x $
Let $y$ be a function g(x):
$3x + 1 + y = 6 - \frac{1}{2}x $
$y = 6 -1 -3x - \frac{1}{2}x $
$y=5 -3\frac{1}{2}x$
Therefore, $g(x) =5 -3\frac{1}{2}x$
