Question

Given the following functions f(x) and g(x), solve (f + g)(3) and select the correct answer below:

f(x) = 2x + 21

g(x) = x − 24

Answer 1

(f+g)(x) = 2x+21 +x-24 = 3x -3 now put x=3 in order to find (f+g)(3) (f+g)(3) = 3(3) -3 = 9-3 = 6, i hope this helps

Answer 2

Let f(x) and g(x) be the function then;

`(f+g)(x) = f(x)+g(x)`

Given the functions:

`f(x) = 2x+21`

`g(x) = x-24`

Solve for :
`(f+g)(3)`

`(f+g)(3) = f(3)+g(3)` .....[1]

Put x = 3 in f(x) and g(x) we have;

`f(3) = 2(3)+21 = 6+21 = 27`

and

`g(3) = 3-24 = -21`

Substitute these values in [1] we have;

`(f+g)(3) =27 +(-21) = 27-21 = 6`

Therefore, the value of
`(f+g)(3)` is 6