SOLUTION

EXAMPLE 1 Represent relations

Consider the relation given by the ordered pair (–2, –3), (–1, 1), (1, 3), (2, –2), and (3, 1).

a. Identify the domain and range.

The domain consists of all the x-coordinates: –2, –1, 1, 2, and 3. The range consists of all the y-coordinates: –3, –2, 1, and 3.

SOLUTION

EXAMPLE 1 Represent relations

Represent the relation using a graph and a mapping diagram.

b.

b. Graph

Mapping Diagram

EXAMPLE 2

Tell whether the relation is a function. Explain.

Identify functions

a.

SOLUTION

The relation is a function because each input is mapped onto exactly one output.

EXAMPLE 2

Tell whether the relation is a function. Explain.

Identify functions

b.

The relation is not a function because the input 1 is mapped onto both – 1 and 2.

SOLUTION

SOLUTION

GUIDED PRACTICE for Examples 1 and 2

1. Consider the relation given by the ordered pairs (–4, 3), (–2, 1), (0, 3), (1, –2), and (–2, –4)

a. Identify the domain and range.

The domain consists of all the x-coordinates: –4, –2, 0 and 1, The range consists of all the y-coordinates: 3, 1, –2 and –4

SOLUTION

GUIDED PRACTICE for Examples 1 and 2

b. Represent the relation using a table and a mapping diagram.

GUIDED PRACTICE for Examples 1 and 2

2. Tell whether the relation is a function. Explain.

ANSWER Yes; each input has exactly one output.