Julian has a smart phone data plan that costs $40 per month that includes 5 GB of data, but will charge an extra $25 per GB over the included amount. How much would Julian have to pay in a month where he used 3 GB over the limit? How much would Julian have to pay in a month where he used went over by xx GB?

Answer 1

Clearly, the required function is
y = 40 + 25x
So plug in your number.

Answer 2

that is incorrect