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Find the height of any triangle?

  1. Oct 10, 2011 #1
    1. The problem statement, all variables and given/known data

    I have the side lengths of a triangle. The base is 190 ft long, side A is 182 ft long and side B is 363 ft long. That's all I know.

    2. Relevant equations



    3. The attempt at a solution

    I know these side lengths are related somehow.
     
  2. jcsd
  3. Oct 10, 2011 #2
    I'm not 100% sure this is the formula, but try this:
    [itex]h=\frac{2}{c}\sqrt{s(s-a)(s-b)(s-c)}[/itex]
    where
    [itex]s=\frac{a+b+c}{2}[/itex]
     
  4. Oct 10, 2011 #3
    Draw the picture, use the law of sines or cosines to find the angle measures, drawn an altitude, calculate.
     
  5. Oct 11, 2011 #4

    verty

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    Or you could use the fact that you know the distance of the apex from the other two corners to find two equations in x and y.
     
  6. Oct 11, 2011 #5

    SammyS

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    Use the law of cosines to find the angle opposite side B first.
     
  7. Oct 11, 2011 #6

    phinds

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    DRAW THE DAMN PICTURE. All of the other suggestions here are good but if you don't start off by drawing a reasonable picture of what you're working with, you're shooting in the dark.
     
  8. Oct 11, 2011 #7

    SammyS

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    Very true !!!
     
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