"Published in Newark, California, USA"
A surveyor on a mountain peak observes below him two vessels lying at anchor 1 mile apart and in the same vertical plane with his position. He finds the angles of depression of the ships to be 18° and 10° respectively. How high does the peak rise above the water? (1 mile = 5280 feet)
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| Photo by Math Principles in Everyday Life |
Solution:
This is also a great application of angle of depression especially for the surveyors and Civil Engineers. Let's analyze and label further the above figure as follows
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| Photo by Math Principles in Everyday Life |
The above equation becomes
Therefore, the height of a mountain peak from the water is
