Question

Function f is defined by the set {(2, 3), (4, 7), (-1, 5)}. If f is reflected in the line y = x, which point will (-1, 5) now be?

Answer 1

i believe it is referring to inverse functions, and it will be (5,-1)

the domain will be switched with the range, i.e.:

if the function is defined as all points (x,f(x)), where x is any point in the domain and f(x) are all points in the range, then the inverse function (function that can be reflected over line y=x) is defined as (f(x),x))

or more simply put,
f(x) = y such that f^-1(y) = x

Answer 2

You are correct.