Grade 10 mathematics lesson

2. LESSON OBJECTIVE:
Represent organized data
using a line graph.

3. WHAT IS A LINE GRAPH?
 Line graph is a type of graph used to represent
changes in data over a period of time. Usually, data
are represented by points and are connected by line
segments.
 Data like changes in population, temperature, and
profit can be represented by a line graph.
 In general, the horizontal axis is used as the time
axis and the vertical axis is used to show the changes
in the other quantity.

4. HOW DO WE CONSTRUCT A
LINE GRAPH?
1. Identify the variables.
2. Determine the range of values.
3. Determine a scale.
4. Label the graph.
5. Plot the points and connect them.
6. Give the title of the graph.

5. EXAMPLE:
The table below shows the daily temperature in San Luis
recorded for 7 days in °C. Represent the data using a line
graph and answer the questions that follow.
Day Temperature (°C)
1 24
2 29
3 21
4 27
5 30
6 26
7 27
1. Identify the variables.
2. Determine the range values.

6. 3. Determine a scale.
4. Label the graph.
0
4
8
12
16
20
24
28
32
36
1 2 3 4 5 6 7
Temperature
Day

7. 5. Plot the points and connect them.
6. Give the title of the graph.
0
4
8
12
16
20
24
28
32
36
1 2 3 4 5 6 7
Temperature
Day
Daily Temperature in San Luis

8. Q1: What is the line graph about?
0
4
8
12
16
20
24
28
32
36
1 2 3 4 5 6 7
Temperature
Day
Daily Temperature in San Luis

9. Q2: What day has the coldest temperature?
0
4
8
12
16
20
24
28
32
36
1 2 3 4 5 6 7
Temperature
Day
Daily Temperature in San Luis

10. Q3: What day has the hottest temperature?
0
4
8
12
16
20
24
28
32
36
1 2 3 4 5 6 7
Temperature
Day
Daily Temperature in San Luis

11. Q4: What is the difference in temperature of Day 3 and 5?
0
4
8
12
16
20
24
28
32
36
1 2 3 4 5 6 7
Temperature
Day
Daily Temperature in San Luis

12. WHAT’S NEXT???
Represent organized data
using a histogram and an
ogive.