Find g(f(x)) f(x)=-3x g(x)=-x+8

$f (x) = - 3 x$ $g (x) = - x + 8$

Set up the composite result function.

$g (f (x))$

Evaluate $g (- 3 x)$ by substituting in the value of $f$ into $g$ .

$g (- 3 x) = - (- 3 x) + 8$

Multiply $- 3$ by $- 1$ .

$g (- 3 x) = 3 x + 8$