Cell Phone Plans.

Question

A cell phone provider offers plan 1 that costs $40 per month plus $20 per text message recieved. A comparable plan 2 costs $60 per month but offers unlimited text messaging. 

1. What equations can you write to model the situation?

Cell phone plan #2 cost per month_______

Cell phone plan #1 cost per month_______

2. How will graphing the equations help you find the answers?

Answer 1

Cell phone plan #1 cost per month = C1 = $(40 + 20x) where x = # of text messages received

Cell phone plan #2 cost per month = C2 = $60

C1 = C2 will give you the point of intersection of the 2 graphs.

40 + 20x = 60 => x = 1

For 1 text message received, both plan cost the same. For more than 1 text messages received, plan 2 is more beneficial.