8.6 = -5
13.6 = 0
There should be another x value in your equation above, but with what you listen this is correct.
By plugging (k-2) in t, we can write that

The domain would be x ≥ 0.
This is because the outlet cannot have profit before it was open. Therefore, the growth must be from year 0 to present. If they give a year as starting, you can have an upper limit too, but there is not enough information here to determine that information.
Answer:
The two stadiums are approximately 3115.1 meters away from each other
Step-by-step explanation:
Since we can construct two right angle triangles between the blimp and the two stadiums as shown in the attached image, then the distance "x" between the two can be find as the difference between the right triangle legs that extend on the ground.
In order to find the size of such legs, one can use the tangent function of the given depression angles as shown below:

and for the other one:

The the distance between the stadiums is the difference:
b - a = 3405.7 - 290.6 meters = 3115.1 meters