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Geo-Trig question
I loved geo-trig in highschool .... but that was a l o n g time ago.
 I need to know the length of the other two sides of the red triangle. (one side is a known- 20m) If it is hard to read the angles: 35º48' 54º12' 90º thanks !! 
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max |
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11-25-2011, 09:50 AM
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since you've got all of the angles and one side, there are several ways to do it, but the first one that comes to mind
Tangent of an angle = opposite side length over the adjacent side length. Then, once you have 2 sides, use the pythagorean theorem to find the third side c^2=a^2+b^2 I'd try the math, but I'm not sure if you have the triangle drawn wrong but labeled correctly, or if it's drawn correctly and labeled wrong. Based on the drawing, you have the 35° and 54° backwards.
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Steve '08 Boxster RS60 Spyder #0099/1960 - never named a car before, but this is Charlotte. '88 targa  SOLD 2004 - gone but not forgotten
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11-25-2011, 10:14 AM
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You're right masraum, I have the 54º and the 36º mixed up on the diagram.
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11-25-2011, 10:19 AM
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If the 35° is supposed to be at the bottom of the triangle which is how it looks, then
Tangent of 35°48' = X/20 therefore < wrong answer >X = 20 times .72 = 14.42 meters 400 - 208.06 = y^2 y = 13.85 meters < /wrong answer > I've got to stop trying to work and surf at the same time. Yeah, instead of pretending that 20 is the hypotenuse... 20^2 + 14.42^2 = C^2 --> C = 24.66
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Steve '08 Boxster RS60 Spyder #0099/1960 - never named a car before, but this is Charlotte. '88 targa SOLD 2004 - gone but not forgotten
Last edited by masraum; 11-25-2011 at 12:02 PM.. |
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11-25-2011, 10:22 AM
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revised diagram:
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11-25-2011, 10:27 AM
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I cheated. . . but here you go. . .
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'74 911 Red Sunroof Coupe, 3.6L, etc... '76 912 Yellow SPEC 911/911CUP |
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11-25-2011, 10:46 AM
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Here's some info for the smarter guys w/out CAD software. . .
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'74 911 Red Sunroof Coupe, 3.6L, etc... '76 912 Yellow SPEC 911/911CUP |
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11-25-2011, 10:54 AM
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Masraum, since 'y' is the hypotenuse, it's value would have to be greater than the known side of 20m, right??
Tom in Idaho, thank you very much !! max
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11-25-2011, 10:55 AM
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Sorry - left out the important stuff. . . (from here: Trigonometry - Wikipedia, the free encyclopedia)
  
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'74 911 Red Sunroof Coupe, 3.6L, etc... '76 912 Yellow SPEC 911/911CUP |
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11-25-2011, 10:59 AM
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Back in the saddle again
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Quote:
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Steve '08 Boxster RS60 Spyder #0099/1960 - never named a car before, but this is Charlotte. '88 targa SOLD 2004 - gone but not forgotten
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11-25-2011, 11:57 AM
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1980 /1997 Porsche 911 SC/ 993s 3.0 / 3.6
