Answer:
c
Step-by-step explanation:
Work out the composition and see what you get.
[tex](f\circ g)(x)=f(g(x))=f(7x+10)=\dfrac{(7x+10)-10}{7}=\dfrac{7x}{7}=x[/tex]
This is your first clue that the functions are inverses of each other, so we expect that g(f(x)) = x will be true, too. We can work that out to confirm it.
[tex](g\circ f)(x)=g(f(x))=g\left(\dfrac{x-10}{7}\right)=7\left(\dfrac{x-10}{7}\right)+10\\\\=(x-10)+10=x[/tex]
So, the appropriate choice is as shown below.
