If point (4, 5) is on the graph of a function, which equation must be true? f(5)=4 f(5,4)=9 f(4)=5 f(5,4)=1

Answer 1

Because it is assumed that f(x)=y and points are always written (x,y), f(4)=5 is the one that must be true because x=4 and y=5.