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Trig problem

  • Thread starter ooovooos
  • Start date
  • #1
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Homework Statement


[PLAIN]http://img530.imageshack.us/img530/5062/dgsdgsdgs.jpg [Broken]
what is h??

Homework Equations


tan x = sin x/ cos x
cos x = adj/hyp
sin x = opp/hyp


The Attempt at a Solution


uh im not even really sure where to start. i havent done trig in a really really long time. im guessing you have to use trig. and i set the area under the dotted triangle as x so the entire bottom length would be 100 + X but im not even sure how that helps.

Homework Statement





Homework Equations





The Attempt at a Solution

 
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Answers and Replies

  • #2
Borek
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Add one unknown - length of the leg adjacent to 60° angle. You have two unknowns - h and the leg. Can you express tangents of both angles using these unknowns (and known length 100)?
 
  • #3
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^ no offense but the "clue" you gave was so small that i'm just back where I started...confused...didnt really push me in any particular direction. -_-
tan 30 = h / (100 + x) = sqrt 3 over 3
tan 60 = h / x = sqrt 3?
i dont see how that helps.
i tried solving for h using the one that equals tan 60..that turns out to be x times sqrt 3...i plugged that into the first equation...and that just seems way too complicated. I did this type of question two years ago in HS...i am so sure this question isnt supposed to be this complicated.
 
  • #4
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i tried solving for h using the one that equals tan 60..that turns out to be x times sqrt 3...i plugged that into the first equation...and that just seems way too complicated. I did this type of question two years ago in HS...i am so sure this question isnt supposed to be this complicated.
Is this the equation you got?

[tex]\frac{x\sqrt{3}}{100 + x} = \frac{\sqrt{3}}{3}[/tex]

It requires a bit of algebra, but it's not bad.
 
  • #5
Borek
Mentor
28,444
2,840
i tried solving for h using the one that equals tan 60..that turns out to be x times sqrt 3...i plugged that into the first equation...
You got to two equations in two unknowns, and you are solving them using correct approach. Just don't give up.
 

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