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Trig problem

  1. Sep 4, 2010 #1
    1. The problem statement, all variables and given/known data
    [PLAIN]http://img530.imageshack.us/img530/5062/dgsdgsdgs.jpg [Broken]
    what is h??

    2. Relevant equations
    tan x = sin x/ cos x
    cos x = adj/hyp
    sin x = opp/hyp

    3. 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.
    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Sep 4, 2010 #2


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    Staff: Mentor

    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)?
  4. Sep 4, 2010 #3
    ^ 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.
  5. Sep 5, 2010 #4
    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.
  6. Sep 5, 2010 #5


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    Staff: Mentor

    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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