Concept explainers
Reminder Round all answers to two decimal places unless otherwise indicated.
8. Cell Phone Charges One cell phone plan charges a flat monthly rate of
a. Choose letters to represent the variables.
b. Write a formula to express the cell phone charges as a function of the number of text messages (assume that the number is at least
c. Use functional notation to show the cost of the cell phone if you have
d. Write the formula to express the cell phone charges, this assuming that the number of text messages is less than
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