SOLUTION: A cliff is 80 feet above the sea. From the cliff the angle of depression to a boat is 35°. How far is the boat from the base of the cliff? Round your answer to one decimal place.

Algebra ->  Customizable Word Problem Solvers  -> Geometry -> SOLUTION: A cliff is 80 feet above the sea. From the cliff the angle of depression to a boat is 35°. How far is the boat from the base of the cliff? Round your answer to one decimal place.      Log On

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Question 585918: A cliff is 80 feet above the sea. From the cliff the angle of
depression to a boat is 35°. How far is the boat from the base
of the cliff? Round your answer to one decimal place.
I don't get this either. Teachers and tutors have tried to help me but they don't explain it in a way that I can comprehend it.

Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!


The object BELOW is the boat and the object ABOVE is the top of the
cliff.

The angle of DEPRESSION is the horizontal from an object ABOVE looking
DOWNward to an object BELOW.

The angle of ELEVATION is the horizontal from an object BELOW looking 
UPward to an object ABOVE.

They are always the same angle because they are alternate interior angles
formed when a tranversal (the line of sight) cuts two parallel (horizontal) lines.

So they are both 35°.

In the right triangle, the side opposite 35° is 80 and the side adjacent
35° is x which is what we are to find, so the trig ration that involves
what we are given *the opposite) and what we are to find *the adjacent
is tangent which is OPPOSITE%2FADJACENT 

tan(35°) = 80%2Fx

Multiply both sides by x

x·tan(35°) = 80

Divide both sides by tan(35°)

x = 80%2Ftan%28%2235%B0%22%29 = 114.24 feet

Edwin