Lesson 5: Interpreting Line Graphs

Where Have You Used/Seen Line Graphs Before?

What is a Line Graph???

• Used to show trends in data OVER TIME• Points are plotted and a line is drawn to connect the

points• EVERY POINT ON THE LINE SHOULD HAVE A

VALUE!!!• All line segments must be the SAME LENGTH!

What Do You See in this Line Graph?

Independent and Dependent Variables

• Independent (Controllable) Variable - X variable – Located on X-axis - YOU control this - ex: Time, Months of the year

• Dependent (Uncontrollable) Variable - Y variable – Located on Y-axis - You CANNOT control this - ex: Temperature

Attributes of a Line Graph• What are attributes? - A collection of things needed in order for something to

happen - ex: Cars, Sports

• ATTRIBUTES NEEDED WHEN DEALING WITH LINE GRAPHS!!!

- Title - Axis (X and Y) - Intervals (Range of #s, ex: 1-5) - Scale (Appropriate one needed) - Skew – Inappropriate scale used - Misleads information (Graph may look too big

or too small because scale is too big or too small

Different Ways to Show Line Graph Data

• Continuous Data - The points on a graph are JOINED - “Connect the dots” - Every point is meaningful

• Discrete Data - Points are NOT JOINED - Every single point is not relevant - ex: DVD sales

What is a Table of Values?

• A table that contains data “values”

• Shows trends/relationships about data

Example

See Handout!!!

Create a Line Graph From the Following Table of Values

SEE HANDOUT GIVEN TO YOU BY MR. DOUCETTE!!!

Create a Table of Values from the Line Graph

What Relationships Do You See in the Graphs/Table of Values???

• What do I mean by relationships? - Comparing the data to show trends over

time

• What are the graphs showing?• What questions can be answered by

looking at the graphs?• Are there any patterns you see from the

data?

Make a Line Graph

• How much sleep did you get last week?

• Put the data in a table of values then construct a line graph based on your findings!

• What conclusions can you make based on your data?

Journal Writing

• Where do we see patterns in everyday life? Explain

- Ex: Nature, clothing etc.

• Why/Why didn’t you like our Twister game? Explain

Questions!!!

• Do together: A-G page 127

• Questions 1-5 page 129