help asap thank you

Question

A pilot wants to arrive at her destination as soon as possible. Air traffic is busy, so she can take off 15 minutes later than expected and will be able to travel two times faster than expected if she waits. Create an equation to represent her total travel time, including wait time, where x is the number of minutes the flight was expected to take.

A. y = 2x + 15

B. 

C. 

D. y = 2x − 15

Answer 1

Hi Keef 6,

A way to make this problem easier to understand is to assign a value to the value of X, the original expected travel time. Let's pretend that the flight was originally expected to be a 120 minute trip, so X = 120.

The problem describes that the pilot is forced to wait 15 minutes, and then travels twice as fast the original speed of the flight, so the faster trip only takes 60 minutes total (as it is half the original value of 120). 15 + 60 = Y = 75

So write it out in plain English: The pilot has 15 minutes of waiting plus 60 minutes of travel (AKA half of X)

Solution B, written as y = 0.5*X + 15, is the answer that accurately describes the pilot's travel. You can prove this fact by plugging in your value for X:

Y = 0.5*(120) + 15 = 75, as we proved earlier