EXAMPLE 2 Making a Line Graph

EXAMPLE 2 Making a Line Graph Population

EXAMPLE 2 Making a Line Graph Population The table below shows the population of Austin County in southeast Texas from 1920 to Make a line graph of the data.

EXAMPLE 2 Making a Line Graph Population The table below shows the population of Austin County in southeast Texas from 1920 to Make a line graph of the data.

EXAMPLE 2 Making a Line Graph STEP 1 Make a list of ordered pairs. Think of each column in the table as an ordered pair: (year, population)

EXAMPLE 2 Making a Line Graph STEP 1 Make a list of ordered pairs. Think of each column in the table as an ordered pair: (year, population) ( 1920, 18, 874 ), ( 1930, 18, 860 ), ( 1940, 17, 384 ), ( 1950, 14, 663 ), ( 1960, 13, 777 ), ( 1970, 13, 831 ), ( 1980, 17, 726 ), ( 1990, 19, 832 )

EXAMPLE 2 Making a Line Graph STEP 2 Choose a scale that includes all the population values in your table.

EXAMPLE 2 Making a Line Graph STEP 2 Choose a scale that includes all the population values in your table. STEP 3

EXAMPLE 2 Making a Line Graph STEP 2 Choose a scale that includes all the population values in your table. STEP 3 Graph each point.

EXAMPLE 2 Making a Line Graph STEP 2 Choose a scale that includes all the population values in your table. STEP 3 Graph each point. STEP 4

EXAMPLE 2 Making a Line Graph STEP 2 Choose a scale that includes all the population values in your table. STEP 3 Graph each point. STEP 4 Draw line segments to connect the points.

GUIDED PRACTICE for Example 2 In Exercises 5 and 6, use the graph above. In which year was Austin County’s population the greatest? 5.

ANSWER GUIDED PRACTICE for Example 2 In Exercises 5 and 6, use the graph above. In which year was Austin County’s population the greatest?

ANSWER GUIDED PRACTICE for Example 2 In Exercises 5 and 6, use the graph above. In which year was Austin County’s population the greatest? 5. 6.Over which decades did the population have its greatest increase? How can you tell from the graph? 1990

ANSWER GUIDED PRACTICE for Example 2 In Exercises 5 and 6, use the graph above. In which year was Austin County’s population the greatest? 5. 6.Over which decades did the population have its greatest increase? How can you tell from the graph? 1970 to The segment between 1970 and 1980 shows the steepest angle of incline. 1990

EXAMPLE 3 Comparing Graphs

Radio Stations EXAMPLE 3 The two graphs below both show the number of AM radio stations in the United States. The first uses a full scale. The second uses a broken scale, deleting values between 0 and Compare the graphs. Comparing Graphs

EXAMPLE 3 Comparing Graphs

EXAMPLE 3 Comparing Graphs

SOLUTION EXAMPLE 3 Both graphs are accurate displays. Comparing Graphs

SOLUTION EXAMPLE 3 Both graphs are accurate displays. The number of AM radio stations is declining. The full scale shows that the decline is very slow. Comparing Graphs

SOLUTION EXAMPLE 3 Both graphs are accurate displays. The number of AM radio stations is declining. The full scale shows that the decline is very slow. The broken scale makes the data easy to read, but makes the decline seem sharper than it is. Comparing Graphs