Question

Austin purchased a prepaid phone card for $45.75. Calls cost 25 cents a minute using this card. The credit, C (in dollars), left on the card after it is used for x

minutes of calls is given by the following.
C=45.75-0.25x
How much credit is left on the card after Austin uses it for 30 minutes of calls?

Answer 1

x=-4C+183

here is your answer.