In this section, you will review graphing ordered pairs of points that represent data from a proportional relationship.

Graphing ordered pairs on a coordinate plane is an important way to visually represent the relationship between the two variables in a set of data.

To practice graphing ordered pairs of data, consider the situation below.

Melanie works as a courier. She made a chart of the distances that she drove one day and the time that it took her to drive each distance.

Use the interactive below to practice plotting ordered pairs of rational numbers. For each of the given points, drag the point to the location indicated by the coordinates next to the point.

Use the graph to answer the questions below.

• How do the points on the graph compare to the line?

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  Check Your Answer

  The points all appear to lie on the line.

• Does the line pass through the point (0, 0)? What would this ordered pair represent in the context of Melanie’s situation?

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  Check Your Answer

  Yes. (0, 0) represents Melanie driving 0 miles in 0 hours.

• How many miles did Melanie drive in 1 hour?

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  Check Your Answer

  40 miles

• What is the unit rate for this situation?

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  Check Your Answer

  40 miles per hour, or 40 miles over 1 hour 40 miles 1 hour

Pause and Reflect

How can you identify the unit rate from the graph of a proportional situation?

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Check Your Answer

If the graph is of a proportional situation, divide the y-values by the x-values for each point on the graph. Those ratios are the unit rate.

Practice

1. Rachel recorded the number of pages that she read in particular amounts of time. Graph the data from the table below. Use an online graphing tool or graph paper.
   

   Number of Hours, x	0.5	1	1.5	3
   Number of pages, y	30	60	90	180

   
   
   Interactive popup. Assistance may be required.

   Need a hint?

   Which variable belongs on the horizontal axis? Vertical axis?
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   Check Your Answer

   
2. For the data in question 1, what is the unit rate, in pages per hour, at which Rachel can read?

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   Need a hint?

   How many pages can Rachel read in 1 hour?
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   Check Your Answer

   60 pages per hour