Answer:
{(0, 0), (1, 2), (2, 4), (3, 4)}
Explanation:
A set of ordered pairs that represent a function is one in which each different ordered pair has a unique x-coordinate (so no two different ordered pairs can have the same x -coordinate).
Therefore, {(0, 0), (1, 2), (2, 4), (3, 4)} is a function as each different ordered pair has a unique x-coordinate.
The other sets all have different ordered pairs that share the same x-coordinate and so these sets do not represent functions.
The vertical line test is also used to determine whether a graph represents a function. If the vertical line intersects the graph only once, then the curve represents a function. This test can be applied to ordered pairs, in that if two ordered pairs have the same x-coordinate but different y-coordinates, they will be on the same vertical line and therefore do not represent a function.