Computer-Based Algebra title

What is a System of Equations?

A system of equations is two or more equations where the variables represent the same things. For example, in the "Graphing in Excel" video, the "x" was the additional minutes and the " y" was the total cost in both cell phone plans.

Systems of equations are useful because it makes it easier to compare relationships.

Cell Phone Graph image

 

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Copy and paste the questions below into your email.
Then, write your answer to each question in the email.

For the subject of your email, type Cell Phone Plans.

Use the graph above to answer these questions.

1. If you don't use any additional minutes, which cell phone plan is cheaper?

2. How much money would you save if you don't use any additional minutes and you had the plan you chose in question #1?

3. If you use 120 additional minutes, which cell phone plan is cheaper?

4. How much money would you save if you use 120 minutes and you had the plan you chose in question #3?

5. At one place on the graph, the cell phone plans cost exactly the same amount of money. How much money is it?

6. Estimate the number of additional minutes for question #5.

You were able to answer the questions above because the two lines had variables that represent the same things, minutes and total cost. This is a system of equations.

Activity 2: Paying the Plumber


Site Map: Home>Algebra Units>Systems of Equations>Systems Overview

Activity 1: Comparing Cell Phone Plans

Links

NM Public Education Dept.
Albuquerque Public Schools
Del Norte High School
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