Question

If f(x) = 2x + 3 and g(x) = 3x - 9, find f(g(x)).

Answer 1

Answer:

6x-15

Step-by-step explanation:

First plug in 3x-9 for x

2(3x-9) +3

Multiply 2 by (3x-9)

2(3x-9)=6x-18

add 3

6x-18+3=6x-15

hope this helps :)

Answer 2

Answer:

$\boxed{\sf f(g(x)) = 6x -15 }$

Given:

$\sf f(x) =2x + 3 \\ \sf g(x) = 3x - 9$

To find:

$\sf f(g(x))$

Step-by-step explanation:

$\sf Evaluate \ f(g (x)) \ by \ substituting \ in \ the \\ \sf value \ of \ g(x) \ into \ f(x): \\ \sf f(3x - 9) = 2(3x - 9) + 3 \\ \\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \sf = (2 \times 3x) - (2 \times 9) + 3 \\ \\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \sf = 6x - 18 + 3 \\ \\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \sf = 6x - 15$