SOLUTION: To measure a stone face carved on the side of a mountain, two sightings 800 feet from the base of the mountain are taken. If the angle of elevation to the bottom of the face is 28

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Question 546217: To measure a stone face carved on the side of a mountain, two sightings 800 feet from the base of the mountain are taken. If the angle of elevation to the bottom of the face is 28 degrees and the angle of elevation from the top of the face is 31 degrees, what is the height of the stone face?
*I really do not even know where to begin with this problem

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
To measure a stone face carved on the side of a mountain, two sightings 800 feet from the base of the mountain are taken. If the angle of elevation to the bottom of the face is 28 degrees and the angle of elevation from the top of the face is 31 degrees, what is the height of the stone face?
**
From a point A, draw a horizontal line to point B
From a point B, draw a vertical line to point C
From point A draw a line 28º from horizontal to a point D on the vertical line
From point A draw another line 31º from horizontal to a point C on the vertical line
You now have 2 right triangles, ABC and ABD.
AB=800 ft
Height of stone face=BC-BD
tan 28º=BD/AB=BD/800
BD=800 tan 28º≈425.37
..
tan 31º=BC/AB=BC/800
BC=800 tan 31º≈480.69
..
Height of stone face=BC-BD=480.69-425.37≈95.32 ft