Exercise 1 Page 312

A mapping diagram illustrates how each element in the domain is paired with an element in the range. An ordered pair is a set of numbers written in the form (x,y), where x is a number from the input and y is a number from the output.

Looking at where the arrows start and end, we can see the x-coordinates and their corresponding y-coordinates. We get the ordered pairs by pairing these values. (2,9), (4,9), (6,10), (8,11) For a relation to be a function, each x-value can only be paired with one y-value, but one y-value can be paired with multiple x-values. In a mapping, the x-values in the input can only point to one y-value in the output.

In the given mapping, we can see that none of the x-values correspond to multiple y-values. Since all of the values in the domain only point to one value in the range, the relation is a function.