1. 3-1 Representing Relations
Algebra Glencoe McGraw-Hill Linda Stamper

2. The table shows the results of a canned food drive.
Room #
# students
# cans 18 25
133 20 22
216 24
148
195 26 74 30 21
150
You can write the data in the table as a relation, a set of ordered pairs.
{(25,133),(22,216),(24,148), (22,195),(20,74), (21,150)}
The first coordinate of each ordered pair is the number of students in a homeroom. The second coordinate is the number of cans the students in that homeroom collected.

3. The table shows the results of a canned food drive.
Room #
# students
# cans 18 25
133 20 22
216 24
148
195 26 74 30 21
150
You can write the data in the table as a relation, a set of ordered pairs.
{(25,133),(22,216),(24,148), (22,195),(20,74), (21,150)}
The braces indicate that these are all the ordered pairs in this relation.
The braces indicate that these are all the ordered pairs in this relation.

4. List in numerical order!
The table shows the results of a canned food drive.
Canned Food Drive
Room #
# students
# cans 18 25
133 20 22
216 24
148
195 26 74 30 21
150
You can write the data in the table as a relation, a set of ordered pairs.
{(25,133),(22,216),(24,148), (22,195),(20,74), (21,150)}
The first coordinates are the domain of the relation.
Domain: {20, 21, 22, 24, 25}
List in numerical order!

5. List in numerical order!
The table shows the results of a canned food drive.
Canned Food Drive
Room #
# students
# cans 18 25
133 20 22
216 24
148
195 26 74 30 21
150
You can write the data in the table as a relation, a set of ordered pairs.
{(25,133),(22,216),(24,148), (22,195),(20,74), (21,150)}
The second coordinates are the range of the relation.
Range: {74, 133, 148, 150, 195, 216}
List in numerical order!

6. A relation (a set of ordered pairs) can be represented by a table, a graph, or a mapping.
{(4,1), (2,4), (-4,1), (2,-5), (0,-3), (-3,-3)}
Table
Graph
Mapping x y x y 4 1 2 -4 -5 -3 • 4 2 -4 -3 1 4 -5 -3 • • x
List the x-coordinate in the first column and the y-coordinate in the second column. • • • y

7. A relation (a set of ordered pairs) can be represented by a table, a graph, or a mapping.
{(4,1), (2,4), (-4,1), (2,-5), (0,-3), (-3,-3)}
Table
Graph
Mapping x y x y 4 1 2 -4 -5 -3 • 4 2 -4 -3 1 4 -5 -3 • • x • • • y
Determine the domain and range of the relation.
Domain: {-4,-3,0,2,4}
Range: {-5,-3,1,4}

8. Example 1 Express the relation as a table, a graph, and a mapping
Example 1 Express the relation as a table, a graph, and a mapping. Then determine the domain and range.
{(4,3), (-2,-1), (4,-1), (-3,2), (2,-4), (0,-4)}
Table
Graph
Mapping x y x y 4 3 -2 -1 -3 2 -4 • 4 -2 -3 2 3 -1 2 -4 • x • • • • y

9. Example 1 Express the relation as a table, a graph, and a mapping
Example 1 Express the relation as a table, a graph, and a mapping. Then determine the domain and range.
{(4,3), (-2,-1), (4,-1), (-3,2), (2,-4), (0,-4)}
Table
Graph
Mapping x y x y 4 3 -2 -1 -3 2 -4 • 4 -2 -3 2 3 -1 2 -4 • x • • • • y
Domain: {-3,-2,0,2,4}
Range: {-4,-1,2,3}

10. Class Work
Skills Guide Page 6 and Practice Page 9.

11. Homework
3-A2 Pages # 7-17, (Do not need to write the inverse of the relation.)