Question

4. You are getting a new data plan with AT&T for your smartphone. The cost for the data plan of 4GB

is $37.00 a month and $10 charge for each GB over your plan.
(a) Write an equation that defines C(x) as the cost of the cellphone bill per month, and define the
variable x.
er to the nearest tenth of a GB.

Answer 1

1. For x≥4: C(x) = $37.00/month + $10(x-4)

2. For x≤4: C(x) = $37.00/month

Explanation:

Lets define x as the actual number of GB of data used in a month.

C(x) is the total cost of the plan for x GB of data.

The base cost is $37.00/month, which includes 4GB of data.

We can write two equations with for different conditions of x, the number of GB used.:

1. For x≥4: C(x) = $37.00/month + $10(x-4)

2. For x≤4: C(x) = $37.00/month