# Help needed with trigonometric word problem

#### amd123

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

2. Homework Equations

3. 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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#### symbolipoint

Homework Helper
Gold Member
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.

#### amd123

Oh thank god, if it works I owe you BUT i dont 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???

#### symbolipoint

Homework Helper
Gold Member
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.

#### amd123

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.

#### Mark44

Mentor
Oh thank god, if it works I owe you BUT i dont 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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