#### harpazo

##### Junior Member

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- Jan 31, 2013

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Geometry Essentials

Michael Sullivan

Textbook: College Algebra Edition 9

The deck of a destroyer is 100 feet above sea level. How far can a person see from the deck?

A similar question (using different numbers) found online provided the following information:

"The mathematically correct formula is d^2 = 2*r*h where d is the distance to the horizon, r is the radius of the earth, and h is the height above sea level, all in the same units."

Hint Provided by Sullivan:

Earth's radius = 3960 miles

I basically plug and chug.

d^2 = 2(3690)(100)

d^2 = 792,000

sqrt{d^2} = sqrt{792,000}

d = 889.9438184515

My answer is as follows:

A person standing on the deck of a destroyer 100 feet above sea level can see about 889.94 feet. What do you say?