Chapter 7 Section 1

1
Chapter 7 Section 1

• Qualitative Graphing

2
Usefulness of Graphs

• A graph can be used as a form of communication.
• For example, a graph can describe the speed of an
  object, the growth of a child or even a ride on a
  roller coaster.
• For such situations, instead of creating an
  exact picture, you can use a qualitative graph.

3
Usefulness of Graphs

• When you must interpret a qualitative graph to
  solve a problem, a good strategy for
  understanding is to act it out.
• Acting out the problem or possible solutions can
  mean that you physically go through the motions
  described or that you use objects to represent
  the elements of the problem.

4
What is a Qualitative Graph?

• A qualitative graph communicates information
  about situations such as the speed of a car and
  the distance from home when traveling.

5
What does this graph show?
18
16
Water in a bathtub
14
12
Height of Water
10
8
6
4
2
Inches
0 2 4 6 8 10 12 14 16 18
Time
Minutes
6
The graph shown provides information about water
in a bathtub.

• a. What is represented by the horizontal axis?
  the vertical axis?
• b. What does the line moving upwards represent?
• c. What does the horizontal segment of the graph
  represent?
• d. What does the line moving downwards represent?
• e. What is the total time spent from turning on
  the water until the bathtub is empty?

7
Solve the Problem

• a. The horizontal axis represents time in
  minutes. The vertical axis represents the water
  height in inches.
• b. The line moving upwards represents filling the
  bathtub with water.
• c. The horizontal segment represents the time
  between filling and draining the tub with nothing
  else added to it.
• d. The line moving downwards represents draining
  the water from the bathtub.
• e. The total time is 16 min.

8
What is represented by the horizontal axis?
What is represented by the vertical axis?
d
Distance
c
b
a
0
Time
9

• What is represented by each segment?
• Can you tell a story based on the graph?

d
Distance
c
b
a
0
Time
10
The speed of a roller coaster as it goes steadily
up, then faster down a hill.
Speed
Time
11
Your distance from the ground as you swing on a
swing.
Distance
Time
12
The amount of popcorn in a bowl during a movie.
Popcorn
Time
13
Distance from home when returning from a vacation.
Distance
Time
14
Your speed on a bike as you ride up a hill, rest,
then ride down the other side.
Speed
Time
15
Distance covered by a jogger on her daily run.
Distance
Time
16
Heart rate during an aerobics class.
BPM
Time
17
Speed of a bicyclist on a trip that included one
stop for lunch
Speed
Time
18
Graphs are pictures of relationships between
things. In this video , graphs are used to show
movements in different sports. You will learn how
graphs can be used to present many types of
information, including recording one's height and
weight, or predicting the weather.