Answer:
(6) The functions f and g are not inverses
Step-by-step explanation:
You want to know which of several statements proves f(x) = (9x+9)/7 and g(x)=(7x+9)/9 are inverses of each other.
Inverse functions
The inverse of f(x) can be found by solving ...
x = f(y)
x = (9y +9)/7
7x = 9y +9
7x -9 = 9y
y = (7x -9)/9
The plus sign in f(x) turns into a minus sign in its inverse function. g(x) is not the inverse of f(x).
The functions f and g are not inverses.
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Additional comment
As answer choice (2) suggests, graphs of inverse functions will be reflections of each other in the line y=x. The attached graph shows they are not, hence f(x) is not the inverse of g(x).