Identify functions

A function is a relation where each input has exactly one output. You can identify functions from a set of points, a table, or a graph (using the vertical line test).

Do this: Read the concept below, then try the quiz or activity.

Function: Each x-value is paired with only one y-value.
*   {(1,2), (2,4), (3,6)} is a function.
*   {(1,2), (1,3), (2,4)} is NOT a function, because the input 1 has two different outputs.