Question

If `f(x) = 8-10x` and `g(x)=5x+4`, what is the value of `(fg)(-2)`?

Answer 1

-168

Explanation:

Just to be clear, I'm interpreting

`(fg)(-2)`

as

`(fg)(-2)= f(-2)\times g(-2)`.

We can calculate each of these smaller bits using the definitions of the functions you gave in the question with `x=-2`.

`f(-2)=8-10(-2)=8+20=28`
`g(-2)=5(-2)+4=-10+4=-6`

Then, the question becomes:
`(fg)(-2) = 28\times -6 =-168`