Question

Let f(x)=3x-7 and g(x)= -2x - 6, how do you find (f o g)(4)?

Answer 1

`(f@g)(4) = -49`

Explanation:

You can solve this in two ways:
`(1).` plugging the `4` into `g(x)` and then putting what you get from that in to `f(x)`
`(2).` plug `g(x)` into `f(x)` and then plug in the `4`

Option 1:

Plug `4` into `g(x)`:

`g(x) = -2(color(blue)(4))-6 = -8-6 = -14`

Then plug `g(x)` into `f(x)`:

`f(x) = 3(color(blue)(-14))-7 = -42-7 = -49`

Option 2:

Plug `g(x)` into `f(x)`:

`f(x) = 3(color(blue)(-2x-6))-7 = -6x-18-7 = -6x-25`

Finally plug `4` into our current `f(x)`:

`f(x) = -6(color(blue)(4))-25 = -24-25 = -49`