Answer:
Explanation:
Let y be the altitude and x the distance the plane travels from the point of the 35600 ft altitude location (x=0 at that point)
y = 35600 - 3200x
It would be nice to use time instad of distance, but there is no speed of the plane give. It's altitude is espressed only on the basis of miles traveled. If the elevation change were given in feet per minute, or some other unit of time, we can write an equation with time as the x variable.
This equations says:
1) the plane starts at 35,600 ft (since x = 0, the result is 35,600 feet).
2) it descends 2,300 ft for every mile traveled from x = 0.
The unit rate of change is 3200 feet/mile.
The graph is attached.