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

2. EXAMPLE 1
Represent relations
Represent the relation using a graph and a mapping diagram. b.
SOLUTION
b. Graph
Mapping Diagram

3. EXAMPLE 2
Identify functions
Tell whether the relation is a function. Explain. a.
SOLUTION
The relation is a function because each input is mapped onto exactly one output.

4. EXAMPLE 2
Identify functions
Tell whether the relation is a function. Explain. b.
SOLUTION
The relation is not a function because the input 1 is mapped onto both – 1 and 2.

5. 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.
SOLUTION
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

6. GUIDED PRACTICE
for Examples 1 and 2
b. Represent the relation using a table and a mapping diagram.
SOLUTION

7. GUIDED PRACTICE
for Examples 1 and 2
2. Tell whether the relation is a function. Explain.
ANSWER
Yes; each input has exactly one output.