then a certain amount of money per megabyte (MB) of data used on the phone. If a customer uses 35 MB, the monthly cost will be $25.25. If the customer uses 120 MB, the monthly cost will be $38.00.
Find a linear equation for the monthly cost of the data plan,
,as a function of the number of MB used.
Use your equation to find the total monthly cost if 300 MB are used.