1. 1-7 Line Graphs Warm Up Problem of the Day Lesson Presentation
Course 2

2. Course 2
1-7
Line Graphs
Warm Up
1. What is the x-coordinate of the point (2, 3)?
2. To plot the point (3, 7) you would move right ___ units then up ___ units.
3. To plot the point (4, –5) would you move left or right first? 2 3 7
right

3. 1-7 Line Graphs Problem of the Day
Course 2
1-7
Line Graphs
Problem of the Day
Find three mistakes on the graph shown.
Trucks Sold
The line does not connect all the sales. 8 7 6 4 3 2
The intervals on the vertical scale are not equal.
Number of trucks sold
The data for Tuesday shows sales of 6.5 trucks.
Mon Tues Wed Thurs Fri
Days of week

4. 1-7 Line Graphs Learn to display and analyze data in line graphs.
Course 2
1-7
Line Graphs
Learn to display and analyze data in
line graphs.

5. Course 2
1-7
Line Graphs
Vocabulary
line graph
double-line graph

6. Course 2
1-7
Line Graphs
You can use a line graph to show how data changes over a period of time.
A line graph uses line segments to connect data points. The result is a visual record of change.

7. Additional Example 1: Making a Line Graph
Course 2
1-7
Line Graphs
Additional Example 1: Making a Line Graph
Make a line graph of the data in the table. Use the graph to determine during which 2-hour period did the temperature change the most?
Time A.M. 1 P.M. 3 P.M. 5 P.M.
Temperature °F °F °F °F

8. Additional Example 1 Continued
Course 2
1-7
Line Graphs
Additional Example 1 Continued
Time A.M. 1 P.M. 3 P.M. 5 P.M.
Temperature °F °F °F °F
Step 1: Determine the scale and interval for each axis.
Place units of time on the horizontal axis.
95 °F
90 °F
85 °F
80 °F
75 °F
11 AM 1 PM 3 PM 5 PM

9. Additional Example 1 Continued
Course 2
1-7
Line Graphs
Additional Example 1 Continued
Time A.M. 1 P.M. 3 P.M. 5 P.M.
Temperature °F °F °F °F
Step 2: Plot a point for each pair of values.
Connect the points using line segments.
11 AM 1 PM 3 PM 5 PM
95 °F
90 °F
85 °F
80 °F
75 °F

10. Additional Example 1 Continued
Course 2
1-7
Line Graphs
Additional Example 1 Continued
Time A.M. 1 P.M. 3 P.M. 5 P.M.
Temperature °F °F °F °F
Step 3: Label the axes and give the graph a title.
Temperatures on a Given Day
11 AM 1 PM 3 PM 5 PM
95 °F
90 °F
85 °F
80 °F
75 °F
Temperature °F
Time

11. Additional Example 1 Continued
Course 2
1-7
Line Graphs
Additional Example 1 Continued
The temperature changed the most between 11 A.M. and 1 P.M.
11 AM 1 PM 3 PM 5 PM
95 °F
90 °F
85 °F
80 °F
75 °F
Time
Temperature °F
Temperatures on a Given Day

12. 1-7 Line Graphs Try This: Example 1 Month Jan Feb Mar Apr
Course 2
1-7
Line Graphs
Try This: Example 1
Month Jan Feb Mar Apr
Homes Sold
Step 1: Determine the scale and interval for each axis. 25 20 15 10 5
Jan Feb Mar Apr

13. 1-7 Line Graphs Try This: Continued Month Jan Feb Mar Apr
Course 2
1-7
Line Graphs
Try This: Continued
Month Jan Feb Mar Apr
Homes Sold
Step 2: Plot a point for each pair of values.
Connect the points using line segments. 25 20 15 10 5
Jan Feb Mar Apr

14. 1-7 Line Graphs Try This: Continued Month Jan Feb Mar Apr
Course 2
1-7
Line Graphs
Try This: Continued
Month Jan Feb Mar Apr
Homes Sold
Step 3: Label the axes and give the graph a title.
Homes Sold 25 20 15 10 5
Number of Homes Sold
Jan Feb Mar Apr
Month

15. 1-7 Line Graphs Try This: Continued
Course 2
1-7
Line Graphs
Try This: Continued
March showed the greatest increase in number of homes sold.
Homes Sold 25 20 15 10 5
Number of Homes Sold
Jan Feb Mar Apr
Month

16. Course 2
1-7
Line Graphs
You can use a line graph to estimate values between data points.

17. Additional Example 2: Using a Line Graph to Estimate Data
Course 2
1-7
Line Graphs
Additional Example 2: Using a Line Graph to Estimate Data
Use the graph to estimate the population of Florida in 1950.
To estimate the population in 1950, find the point on the line between 1940 and 1960 that corresponds to 1950.
The graph shows about 3.5 million people.

18. 1-7 Line Graphs Try This: Example 2
Course 2
1-7
Line Graphs
Try This: Example 2
Use the graph to estimate the population of Florida in 1970.
To estimate the population in 1970, find the point on the line between 1960 and 1980 that corresponds to 1970.
The graph shows about 7.5 million people.

19. Course 2
1-7
Line Graphs
A double-line graph shows change over time for two sets of data.

20. Additional Example 3: Making a Double-Line Graph
Course 2
1-7
Line Graphs
Additional Example 3: Making a Double-Line Graph
The table shows stock prices for two stocks in one week. Make a double-line graph of the data.
Stock A $10 $9 $11 $10 $8
Stock B $6 $12 $8 $14 $14
Mon Tue Wed Thu Fri

21. Additional Example 3: Making a Double-Line Graph
Course 2
1-7
Line Graphs
Additional Example 3: Making a Double-Line Graph
Stock A $10 $9 $11 $10 $8
Stock B $6 $12 $8 $14 $14
Mon Tue Wed Thu Fri
Stock Prices 15 12 9 6 3
Mon Tue Wed Thu Fri
Plot a point for Stock A for each day of the week.
Price ($)
Then, using a different color, plot a point for Stock B for each day of the week.
Day

22. Additional Example 3 Continued
Course 2
1-7
Line Graphs
Additional Example 3 Continued
Stock A $10 $9 $11 $10 $8
Stock B $6 $12 $8 $14 $14
Mon Tue Wed Thu Fri
Stock Prices 15 12 9 6 3
Mon Tue Wed Thu Fri
Connect the points.
Price ($)
Day

23. Additional Example 3 Continued
Course 2
1-7
Line Graphs
Additional Example 3 Continued
Stock A $10 $9 $11 $10 $8
Stock B $6 $12 $8 $14 $14
Mon Tue Wed Thu Fri
Stock Prices 15 12 9 6 3
Mon Tue Wed Thu Fri
Make a key to show what each line represents.
Price ($)
Stock A
Stock B
Day

24. 1-7 Line Graphs Try This: Example 3 Mon Tue Wed Thu Fri Stock Prices
Course 2
1-7
Line Graphs
Try This: Example 3
Stock A $8 $10 $6 $4 $8
Stock B $4 $14 $12 $14 $12
Mon Tue Wed Thu Fri
Stock Prices 15 12 9 6 3
Mon Tue Wed Thu Fri
Plot a point for Stock A for each day of the week.
Price ($)
Then, using a different color, plot a point for Stock B for each day of the week.
Day

25. 1-7 Line Graphs Try This: Example 3 Mon Tue Wed Thu Fri Stock Prices
Course 2
1-7
Line Graphs
Try This: Example 3
Stock A $8 $10 $6 $4 $8
Stock B $4 $14 $12 $14 $12
Mon Tue Wed Thu Fri
Stock Prices 15 12 9 6 3
Mon Tue Wed Thu Fri
Connect the points.
Price ($)
Day

26. 1-7 Line Graphs Try This: Example 3 Mon Tue Wed Thu Fri Stock Prices
Course 2
1-7
Line Graphs
Try This: Example 3
Stock A $8 $10 $6 $4 $8
Stock B $4 $14 $12 $14 $12
Mon Tue Wed Thu Fri
Stock Prices 15 12 9 6 3
Mon Tue Wed Thu Fri
Make a key to show what each line represents.
Price ($)
Stock A
Stock B
Day

27. Hot Air Balloon Heights
Course 2
1-7
Line Graphs
Lesson Quiz
Make a double line graph of the data.
Hot Air Balloon Heights
Time (A.M.) Balloon 1 Balloon 2 6: 6: 6: 6: 7: 7:

28. 1-7 Line Graphs Lesson Quiz Hot Air Balloon Height Height Time (A.M.)
Course 2
1-7
Line Graphs
Lesson Quiz
Hot Air Balloon Height
400
350
300
250
200
150
100 50
Height
Balloon 1
Balloon 2
6:00 6:15 6:30 6:45 7:00 7:15
Time (A.M.)