Page 89 - Math Course 3 (Book 1)

Rates of Change
Mo. 3

Lesson 3 Concept Summary
Rate of Change

Rate of
KEY CONCEPTS: Change Positive zero Negative
1. Find rates of change.
2. Solve problems involving rates of change.
Real-life
Meaning increase no change decrease

Slants horizontal Slants
MO. 3 - L3a upward line downward
y y y
Graph
Finding Rates of Change

0 x 0 x 0 x
Vocabulary A-Z

Let us learn some vocabulary

Let’s Begin

rate of change
is a rate that describes how one quantity changes Real World Example
in relation to another quantity.
Example

F SCHOOL
2800 C The graph shows Jared’s quiz scores for the first
Vertical Position(ft) 2000 A B D E rate of change from Week 2 to Week 5.
2400
five weeks after he joined a study group. Find the
1600
1200
800
90
400
70
0 200 600 1000 1400 1800 Quiz Scores 80
Horizontal Position(ft) 60
50
change in vertical position 2400 – 2000
1 2 3 4 5 x
change in horizontal position = 800 – 400 0 Number of Weeks
400
= 400 89 – 76 change in quiz score
400 Rate of change = 5 – 2 change in time
or 1ft in vertical position for every 1ft in
400 in horizontal position. ≈ 4.3 Simplify

The rate of change in quiz scores
Answer is an increase of about 4.3 points
per week.

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