Which representation does NOT show y as a function of x?

Me. drysdale earned 906.25 in interest in one year on money that he had deposited in his local bank if the bank paid an interest rate of 6.25% how much money did mr. drysdale deposit

Use composition to determine if (x) or h(x) is the inverse of f(x) for the limited domain x2-1.

Answer! if you don’t mind, can you explain