the angle of elevation from a marker on level ground to the top of a building 100m high is 22degree. Find the distance:
a) from the marker to the base of the building
b) the marker must be moved towards the building so that the angle of elevation becomes 40 degree.

Question

the angle of elevation from a marker on level ground to the top of a building 100m high is 22degree. Find the distance: 
a) from the marker to the base of the building 
b) the marker must be moved towards the building so that the angle of elevation becomes 40 degree.

scooby6363 · Answer

I believe the answer would be 247.5 meters. 
I drew a diagram of the situation:

|dw:1461461996720:dw|

From this I noticed that I will be using tangent because tangent = opposite/adjacent
I then did 100/tan(22 degrees) = 247.5
This can be checked by doing tan^-1(100/247.5) = 22 degrees

elise_kong · Answer

Yes indeed, the answer was right. Thanks @Scooby6363 ! What about question b?

scooby6363 · Answer

You just use the same equation. 100/tan(40 degrees) = 119.175 meters
247.5 - 119.175 = 128.325

So the new distance in order to make the angle of elevation 40 degrees would be 119.175 meters but you would have to move the marker up 128.325 meters up to get to that 119.175 meters.

elise_kong · Answer

@Scooby6363 thank you sooooooo much:)