Which set of ordered pairs represents a function?

{(0, 1), (1, 2), (2, 3), (3, 3)}
{(0, 1), (1, 2), (1, 3), (2, 5)}
{(0, 0), (1, 2), (2, 4), (2, 6)}
{(0, 0), (0, 1), (2, 0), (2, 4)}

Question

Which set of ordered pairs represents a function?

 {(0, 1), (1, 2), (2, 3), (3, 3)}
 {(0, 1), (1, 2), (1, 3), (2, 5)}
 {(0, 0), (1, 2), (2, 4), (2, 6)}
 {(0, 0), (0, 1), (2, 0), (2, 4)}

anonymous · Answer

Do you know what a function is? :)

anonymous · Answer

not really

anonymous · Answer

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anonymous · Answer

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anonymous · Answer

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dessyj1 · Answer

For a function to be a function it must pass the vertical line test. That means for every x value there must be ONLY one y-value. A situation where this theory holds is in a position/time graph. Where time is the x- variable and the position is the y-variable. Would it make sense for an object to be in two different places at lets say 2 seconds?