Question

from the top of a 165 foot lighthouse the angle of depression to a ship in the ocean is 15°. how far is the ship from the base of the lighthouse?

Answer 1

Check the picture below.

`\tan(15^o )=\cfrac{\stackrel{opposite}{165}}{\underset{adjacent}{x}} \implies x\tan(15^o)=165\implies x=\cfrac{165}{\tan(15^o)}\implies x\approx 615.79`

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