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Trigonometry Problem


Date: 11 Aug 1995 00:45:02 -0400
From: Norm
Subject: pythagoras

Question: A 12 metre ladder is inclined to the vertical at 48 degrees.  How
far is if from the base?


Date: 11 Aug 1995 10:29:24 -0400
From: Dr. Ken
Subject: Re: pythagoras

Hello there!

This is a classic example of where Trigonometry is the only tool we have if
we want to solve the problem.  Here's how it goes:

     |\
     | \
     |  \
     |   \
     |    \
     |     \
     |      \
     |       \12 m
     |        \
     |         \
     |          \
     |           \
     |       48deg\
     |_____________\
           x

Now since Cos = Adjacent/Hypotenuse, we know that Cos(48) = x/12.  Since the
Cosine of 48 degrees (in radians, 4Pi/15) is 0.669, we have the equation 
0.669 = x/12.  Multiplying by 12, we see that x = 8.03 meters.

Pretty fun, eh?

-K
    
Associated Topics:
High School Trigonometry

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