Answer:
Using the inverse composition rule you know that if (fog)=x and (gof)=x then the functions are inverses.
( g o f ) = ( 7 x + 1 ) − 1 7 this will result in (gof)=x ( f o g) = 7 x − 1 7 +1 = x − 1 + 1 =x
graphically you can check this if it seems that the functions are reflected over the line x=y.
Step-by-step explanation: