6-7 Line Graphs Warm Up Problem of the Day Lesson Presentation Course 1 Warm Up Problem of the Day Lesson Presentation

Warm Up Describe how to graph each point on a coordinate grid. 1. (4, 5) 2. (0, 2) 3. (3, 0) right 4, up 5 up 2 right 3

Vocabulary line graph double-line graph

Data that shows change over time is best displayed in a line graph Data that shows change over time is best displayed in a line graph. A line graph displays a set of data using line segments.

Population of New Hampshire Additional Example 1: Making a Line Graph Use the data in the table to make a line graph. Population of New Hampshire Year Population 1650 1,300 1670 1,800 1690 4,200 1700 5,000

Because time passes whether or not the population changes, time is independent of population. Always put the independent quantity on the horizontal axis. Caution!

Population of New Hampshire Additional Example 1 Continued Step 1: Place year on the horizontal axis and population on the vertical axis. Label the axes. Step 2: Determine an appropriate scale and interval for each axis. Population of New Hampshire Step 3: Mark a point for each data value. Connect the points with straight lines. 6,000 5,000 4,000 Population 3,000 2,000 Step 4: Title the graph. 1,000 1650 1670 1690 1700 Year

Additional Example 2: Reading a Line Graph Use the line graph to answer each question. A. In which year did CDs cost the most? 2002 B. About how much did CDs cost in 2000? $15 C. Did CD prices increase or decrease from 1999 through 2002? Increase

Check It Out: Example 2 Use the line graph to answer each question. A. In which year did CDs cost the least? 1999 B. About how much did CDs cost in 1999? $13 C. Did CD prices increase or decrease from 2001 to 2002? Increase

Lesson Quiz: Part II Use the line graph to answer each question. 1. Which plant was taller on Tuesday? 2. Which plant grew more between Thursday and Friday? 3. Which plant grew the most in one week? A Each grew the same amount. A

Number of Aluminum Cans Collected Lesson Quiz: Part I 4. Use the data to make a line graph. Number of Aluminum Cans Collected Mon Tue Wed Thu Fri 100 150 200 125 175 50 100 150 200 250 Number of Cans Aluminum Cans Collected M T W Th F