The phone company Splint has a monthly cellular plan where a customer pays a flat monthly fee and then a certain amount of money
per minute used on the phone. If a customer uses 390 minutes, the monthly cost will be $169.5. If the customer uses 920 minutes, the monthly cost will be $355. A) Find an equation in the form y=mx+b, where x is the number of monthly minutes used and y is the total monthly of the Splint plan.
