Real Life Examples of Linear Equations
are All Around us!
CELL PHONE PLANS
Just about everyone has a cell phone, and many rate plans are a near function of some kind. You
pay 30 colars a month for your cell phone and Scents per minute of usage.
Step 1 - Create a hear equation to represent the cost of your cell phone for every minute you
use per month
Step 2 - Create a table to identify how much your monthly bill will be based on the different
minutes.
Minutes
Linear Equation:
Monthly Cost
Ordered pairs
(x, y)
50
100
250
350
130
180
500
750
1000
1500
230
Step 3 - Graph the equation by plotting the ordered pairs. Be sure to label the x and y axis.
Step 4 - Create and draw a picture of the next IPhone.
Step 5 - Answer the following questions
1) Determine if this relation is a function and explain your answer.
2) Identify the slope and what it represents
3) Describe the relationship between minutes and monthly cost.
4) What is the y-intercept of this equation? Explain what the y-intercept means
5)
6)