Laura & Mary are doing their homework together.
Mary thinks the relation {(1, 1), (1, 3), (2, 3), (3, 4)} is a function, but Laura doesn’t think it is.
Who is correct and why?
A function is a relation in which every x-value corresponds with no more than one y-value. In this problem, the x-value 1 has two different answers; this means it is not a function.
Additionally, if you graphed this, it would not pass the vertical line test.