If point (4, 5) is on the graph of a function, which equation must be true?

Question

A f(5)=4

B f(5,4)=9

C f(4)=5

D f(5,4)=1

Answer 1

A point is (x, y).

And a function is f(x) = y.

We get information from the question, x = 4 and y = 5.

So the answer should be C. f(4) = 5.