Answer: The flagpole is about 22.3 feet tall.
This is roughly the size of a two story building, assuming each floor is 10 feet or so.
Since this height is under 25 ft, this flagpole is in compliance with the regulation.
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Work Shown:
The horizontal leg of the triangle is 36 ft. This is the adjacent leg to the reference angle 25 degrees.
The vertical leg of the triangle is x-5.5, and this leg is the opposite side to the reference angle 25 degrees.
Use the tangent rule to connect the opposite and adjacent sides.
Solve for x.
tan(angle) = opposite/adjacent
tan(25) = (x-5.5)/36
36*tan(25) = x-5.5
x-5.5 = 36*tan(25)
x = 36*tan(25)+5.5
x = 22.28707569358
x = 22.3 ft is the approximate height of the flagpole
Make sure your calculator is in degree mode.
The height is not over 25 ft, so this flagpole meets the requirements.