Chapter 2 Section 1
Relations and Functions
Algebra 2 Notes
January 8, 2009
Warm-Ups/Quiz Review!!

Evaluate the expression for the given value:

Simplify by combining like terms

Solve the following equations for x
Quiz Review cont…

A dog kennel owner has 100ft of fencing
to enclose a rectangular dog run. She
wants it to be 5 times as long as it is wide.
Find the dimensions of the dog run.
Chapter 2 Section 1
Graphing a Relation

Relation: a set of pairs of input and output values.You
can write a relation as a set of ordered pairs
Input (x-values)
Relation
{(-2, 4), (3, -2), (-1, 0), (1, 5)}
Output (y-values)

Graph this relation on a coordinate plane
Finding Domain and Range
The domain of a relation is the set of all
inputs.
 The range of a relation is the set of all
outputs.

{(2, 4), (3, 4.5), (4, 7.5), (5, 7), (6, 5), (6, 7.5)}
Identifying a Function


Function: for one domain value (x) there is one and
only one range value (y)
Determine whether or not this relation is a function.
Use a mapping.
{(-1, 2), (3, 6), (-5, -10), (3, 2)}
Domain
-5
-1
3
Range
-10
-2
2
6
Evaluating Functions

Use the following function to find
Homework #3
Chapter 2 Section 1
Pg 59 #1, 2, 7, 12, 13, 16, 17, 20-23, 32,
40-42, 55, 56