1. *Note: You will need graph paper today
Drawing Graphs
Unit 7, Lesson 4
*Note: You will need graph paper today

2. An Example
On December 26, 2004, a massive underwater earthquake rocked the coast of Indonesia’s Sumatra Island. It caused a tsunami, or huge ocean waves.
This table shows the height of the waves at different distances from land.

3. To Display This Data…
1. Draw two axes (one axis, two axes), one horizontal and one vertical. The horizontal axis shows the independent variable, Distance From Land. The vertical axis shows the dependent variable, Height of Waves.
2. Choose an appropriate scale.
Horizontal – Data goes to 30. Count by 5.
Vertical – Data goes to 32. Count by 5. 10 20 30 40
Height of Waves (m)
Distance from Land (km)

4. To Display This Data…
Height of Waves in a Tsunami
3. To mark our first data point, we find 5km on the horizontal axis, and travel up to 32 on the vertical axis. 32 is 2/5 of the way from 30 to 35. Plot the point 2/5 of the way between the lines that represent 30 and 35.
Distance from Land (km)
Height of Waves (m) 10 20 30 40
3a. Continue to mark data points in the same way, by finding the value on the horizontal axis and travelling up to the value of the vertical axis.
4. Because (If) the data is continuous, we can join the points together with a line. If the data is discrete, we do not join the points.
The farther the wave from land, the less the height of the wave.
5. Finally, give your graph a title.

5. Your Turn

6. Does your graph look like this?
Distance Travelled on Road Trip
Title
Time Passed (h)
Distance Travelled (km) 1 2 3 6 5 4 8 7
100
200
300
400
500
600
Data points accurate
Vertical
Scale
Line connecting points
(drawn with a ruler)
Dependent
Variable
Horizontal scale
Independent Variable

7. Practice Makes Perfect
Workbook – p. 94, 95