Find f(g(x)) f(x)=4x , g(x)=x+5

$f (x) = 4 x$ , $g (x) = x + 5$

Step 1

Set up the composite result function.

$f (g (x))$

Step 2

Evaluate $f (x + 5)$ by substituting in the value of $g$ into $f$ .

$f (x + 5) = 4 (x + 5)$

Step 3

Apply the distributive property.

$f (x + 5) = 4 x + 4 \cdot 5$

Step 4

Multiply $4$ by $5$ .

$f (x + 5) = 4 x + 20$