Help needed with trigonometric word problem

  • Thread starter amd123
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  • #1
amd123
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Homework Statement


http://img135.imageshack.us/img135/4150/trighelp.jpg [Broken]

Homework Equations





The Attempt at a Solution


http://img18.imageshack.us/img18/8480/workz.jpg [Broken]

Please help I'm totally confused, if anyone can help I can offer a reward of monetary value :).
 
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Answers and Replies

  • #2
symbolipoint
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You are looking for the point along the 40 foot side at which the height from floor to beam is 16 inches. When you find the value, you want to see if it is more than 2 feet away from the righthand side of the wall.
 
  • #3
amd123
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Oh thank god, if it works I owe you BUT i don't have any idea how to do that :(
Also are my calculations correct? When i subtract 8.6 from 10 i get 1.4 feet but when i take the sin of 6 degrees * h2 i get 4.2 feet for the height of the beam?
 
  • #4
symbolipoint
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Also, since you have a 10 by 40 right-triangle, you should be able to find the measures of the other two angles, and therefore should be able to find the other angle measures in the diagram. Then, you have that lower right-triangle, on the bottom. The angle on the left is easy: the found angle above, the 12 degree, the desired lower angle - their sum is 90 degrees.
 
  • #5
amd123
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Also, since you have a 10 by 40 right-triangle, you should be able to find the measures of the other two angles, and therefore should be able to find the other angle measures in the diagram. Then, you have that lower right-triangle, on the bottom. The angle on the left is easy: the found angle above, the 12 degree, the desired lower angle - their sum is 90 degrees.

NVM, didnt read carefully :(
 
  • #6
36,709
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Oh thank god, if it works I owe you BUT i don't have any idea how to do that :(
Also are my calculations correct? When i subtract 8.6 from 10 i get 1.4 feet but when i take the sin of 6 degrees * h2 i get 4.2 feet for the height of the beam?

The numbers you show are close, but not precise. DON'T ROUND INTERMEDIATE VALUES. The height of the small triangle is not 1.4 ft, and the acute angle of the small triangle is not 6 deg. If you use these values, you will probably get the wrong answer. I have no idea how you got 4.2 ft.
 

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