math
posted by Pauline Duma on .
john is standing 100 metres away from a building.the angle of elevationto the top of the building is8 degrees .He now walks straight away from the building.When he stopes,the angle of elevation is only 1 degree and 48 seconds.How far away is now from the base of the building.

The height H of the building can be found from the equation:
tan(8°)=H/100
or
H=100tan(8°) ....(1)
After he "backedup" to a distance of D from the building, the new relation with the height is:
tan(1°48')=H/D
or
D=H/tan(1°48')....(2)
So substitute H from (1) into (2) to get
D=100tan(8°)/tan(1°48')
Can you take it from here?
(The answer is around 450m)