JoAnn is considering a cell phone plan that includes 450 any

JoAnn is considering a cell phone plan that includes 450 anytime minutes a month for dollar 39.99. Each additional minute is $0.45. write an equation for the monthly bill for this plan in terms of the number of minutes used, assuming that JoAnn talks for more than 450 minutes per month.

Solution

450 miutes charges = $39.99

extra minute charge = $0.45

Lets assume Joann talks for T minutes where T is more than 450

Total bill = $(39.99 + (T - 450)*0.45)