Trigonometry! #105
An observer tall is away from a chimney. The angle of elevation of the top of the chimney from her eyes is . Then find the height of the chimney.
Express your answer in , and enter the numerical part only.
This problem is part of the set Trigonometry .
The answer is 30.
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1 solution
Let ED be the observer. Hence ED= 1.5 m
Let AC be the Chimney. Hence, the distance between AC and ED is 28.5 m
From E, draw a line parallel to DC intersecting AC at B.
^^By doing that we get, ED=BC= 1.5m and EB=DC=28.5m
We're given that AEB= 45 degrees.
In triangle AEB,
tan45=AB/BE
1= AB/28.5
Hence AB=28.5m
Now AC=AB+BC
AC= 28.5+1.5
AC= 30m