Problem: A phone company 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 450 minutes, the monthly cost will be $87.50. If the customer uses 840 minutes, the monthly cost will be $146. (a) Find a linear equation for y, the monthly cost in dollars, of the cell plan as a function of x, the number of monthly minutes used. Be detailed in your response and provide examples also.