Find g(f(x)) f(x)=-7x-8 , g(x)=-2x+9

$f (x) = - 7 x - 8$ , $g (x) = - 2 x + 9$

Step 1

Set up the composite result function.

$g (f (x))$

Step 2

Evaluate $g (- 7 x - 8)$ by substituting in the value of $f$ into $g$ .

$g (- 7 x - 8) = - 2 (- 7 x - 8) + 9$

Step 3

Simplify each term.

Apply the distributive property.

$g (- 7 x - 8) = - 2 (- 7 x) - 2 \cdot - 8 + 9$

Multiply $- 7$ by $- 2$ .

$g (- 7 x - 8) = 14 x - 2 \cdot - 8 + 9$

Multiply $- 2$ by $- 8$ .

$g (- 7 x - 8) = 14 x + 16 + 9$

Step 4

Add $16$ and $9$ .

$g (- 7 x - 8) = 14 x + 25$