The angle of elevation at the top of a building at point A (on level ground) is 62 degrees. At a point 120m away from A, the angle of elevation is found to be 35 degrees. Find the height of the building.
Hello, fActor
From a point A on level ground the angle of elevation to the top of a building is 62^{o}.
At a point 120m away from A, the angle of elevation is found to be 35^{o}.
Find the height of the building.
If you put the point on the building, where is the 35^{o} angle?
There is basically one diagram that satisfies the description.
The observer stands atCode:* T * * | * * | * * | h * * | * 35o * 62o | * - - - - - * - - - - - * B 120 A x :
The angle of elevation to the top of the building is 62^{o}.
He moves 120 m away from (and away from the building) to
Now the angle of elevation to is only 35^{o}.
We want , the height of the building.
Let be the distance from to the base of the building.
We have: .
From [1]: .
From [2]: .
Equate [3] and [4] and solve for