Question

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 420 minutes, the monthly cost will be $104. If the customer uses 720 minutes, the monthly cost will be $164.
A) Find an equation in the form y=mx+b,
y=mx+b,
where x
x
is the number of monthly minutes used and y
y
is the total monthly of the Ringular plan.

Answer 1

(420,104)(720,164)
slope = (164 - 104) / (720 - 420) = 60/300 = 1/5

y = mx + b
slope(m) = 1/5
(420,104)...x = 420 and y = 104
now we sub and find b, the y int
104 = 1/5(420) + b
104 = 84 + b
104 - 84 = b
20 = b

so ur equation is : y = 1/5x + 20