From an aeroplane, at an altitude of 2.3km, the angle of depression of the airport is 32Degrees and the angle of depression of the town is 18degrees (both are in direct line ahead of the plane) How far is the town from the airport?

Answer 1

If we label the diagram as follows:
P = plane
A = point on ground just below the plane
B = airport
C = town

we want to find BC

2.3/AB = tan 32
2.3/(AB+BC) = tan 18
eliminating the AB we have

2.3/tan32 = 2.3/tan18 - BC
Now just solve for BC.