Question

A cell phone company charges $50 for the phone plus a monthly service charge of $30. The equation below describes the total cost y after x months. Which equation below best describes this situation? (A) y = 50x + 30 or (B) y = 30x + 50 or (C) x = 50x + 30 or (D) x 30x + 50

Answer 1

To find total, we'll need to add all the costs! There's the cost for the phone which is paid once, monthly fee for all the months you use it.

total = 50 + (30 × months )

In this case, the question wants the equation in x and y, so we can plug those in:

y = 50 + 30x

Answer 2

answer is 
B. y = 30x + 50

cause 
monthly service charge of $30 means $30 charge each month for x months.
and 50 is one time charge for the phone
and the total cost y after x months