Proportional and and Non-Proportional Relationships in Graphs

Examples, videos, and solutions to help Grade 7 students learn how to decide whether two quantities are proportional to each other by graphing.

Lesson 5 Outcome

• Students decide whether two quantities are proportional to each other by graphing on a coordinate plane and observing whether the graph is a straight line through the origin.
• Students study examples of quantities that are proportional to each other as well as those that are not.

Lesson 5 Summary

When two proportional quantities are graphed on a coordinate plane, the points lie on a straight line that passes through the origin.

NYS Math Module 2 Grade 7 Lesson 5 Exercises and Examples

Opening Exercise
Isaiah sold candy bars to help raise money for his scouting troop. The table shows the amount of candy he sold to the money he received.
Is the amount of candy bars sold proportional to the money Isaiah received? How do you know?

Example 1: From a Table to Graph
Plot a graph from the given table.

Important Note:

Characteristics of graphs of proportional relationships:
In a proportional relationship, the points will all fall on a straight line going through the origin.

Example 2
Plot ordered pairs for all the values of the Opening Exercise.

Example 3
Plot a graph from the given table.

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