one side of a triangular log has a length of 100 feet  TOPIC_SOLVED

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one side of a triangular log has a length of 100 feet

Postby theshadow on Thu Feb 26, 2009 2:31 pm

one side of triangelar lot has a length of 100 feet; the angle opposite that side is 55 degrees. another angle is 63 degrees. how much fence will be needed to enclose the lot? i am having trouble figuring out which angle goes where and if i should use Cos or Tan
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Postby stapel_eliz on Thu Feb 26, 2009 6:07 pm

theshadow wrote:one side of triangelar lot has a length of 100 feet; the angle opposite that side is 55 degrees. another angle is 63 degrees. how much fence will be needed to enclose the lot?

You know that the angle sum for any triangle is 180 degrees, so what is the measure of the one remaining angle?

theshadow wrote:i am having trouble figuring out which angle goes where and if i should use Cos or Tan

When you have the angles and the length of the side opposite one of those angles, it's usually a safe bet that you'll need to use the Law of Sines. :wink:

The actual placement, in your drawing, of the various angle measures is irrelevant. Just draw a triangle, label the angles with their measures, and label the one side with the given length. Then work from the picture to set up your ratios, and solve for the lengths of the other two sides. The sum of their lengths is the amount of fencing needed.

Hope that helps! :D
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Re: one side of a triangular log has a length of 100 feet

Postby theshadow on Fri Feb 27, 2009 5:29 pm

i did 180-55-63=62 then 100/sin55=x/sin63=y/sin62 so x=108.8 y=107.8

is it ok that their about the same?
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  TOPIC_SOLVED

Postby stapel_eliz on Fri Feb 27, 2009 6:56 pm

theshadow wrote:is it ok that their about the same?

Since the angles opposite those sides have nearly the same measures, yes, you should expect those sides to have nearly the same lengths. :wink:
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Re: one side of a triangular log has a length of 100 feet

Postby theshadow on Sat Feb 28, 2009 3:01 pm

ok
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