the answer:
the main formula for finding the value of an ordered pair of the inverse of a function f(x) is as following:
if (x, f(x)) is an ordered pair, so the ordered pair of the inverse of f(x) is (x', y') such that x'=f(x) and y'=x,
therefore, If (9,33) is an ordered pair of the inverse of f(x), the ordered pair of the function f(x) is (33, 9)