The phone company Ringular 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 500 minutes, the monthly cost will be $132. If the customer uses 700 minutes, the monthly cost will be $172.

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 Ringular plan.