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6.2 Plotting Travel
Now that we’ve learned the equation for travel, let’s see how travel can be plotted on a graph.
 Example 6.4: Susan is running in a 10k race. She runs at an average speed of 1/3 kilometer per minute (20 km/hr.).
a.) How far will she travel in 0 minutes, 6 minutes, 12 minutes, 21 minutes, and 30 minutes?
b.) Plot her travel on a graph.
Solution: a.) Equation 6-1 is used to find her distance at each of the times. The distances can be put in a table as shown below:
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d = rt = (1/3)t
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t (min.)
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d (km)
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d = (1/3)0 = 0
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0
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0
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d = (1/3)6 = 2
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6
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2
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d = (1/3)12 = 4
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12
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4
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etc.
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21
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7
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30
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10
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b.) If we plot these points on a graph with time on the x-axis and distance on the y-axis, we can see that they fall into a straight line. Click on the graph below to see how the points are plotted.
Figure 6.1 Plot of Distances versus Time
If we connect the points with a line, we get a line which represents the formula d = rt. Using the xy coordinates with x for time and y for distance, the formula becomes:
where y = distance, in kilometers
x = time, in hours
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