Question 245882
Here's a couple of ways to do this:<ul><li>In a function no two ordered pairs have the same x value <i>and different y values</i>. We have three ordered pairs with the same x, 13. But they all have the same y, 14! So this is a function.</li><li>Plot the points on a graph. (You will end up plotting (13,14) three times (on top of itself) but it still counts as just a single point.) Then look at the graph. There is no vertical line which passes through any two of the points. So this graph, and therefore the relation, passes the vertical line test and is a function.</li></ul>