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Thread: find the triangle

  1. #1
    Junior Member
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    find the triangle

    Find all solutions for each triangle.

    A = 30
    a = 4
    b = 8

    4 / 30 = 8 / SIN B

    4 SIN B = 8 ( SIN30 )

    SIN B = 8 (SIN 30) / 4 = 1

    Did I do that right?
    I know there is only one solution.
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  2. #2
    Banned
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    Yes, you are right.
    $\displaystyle
    =\frac{4}{sin30}= \frac{8}{sinB}
    $

    $\displaystyle
    sinB=1
    $

    $\displaystyle
    B=90
    $

    Now, in right triangle, right angled at B,

    $\displaystyle
    c=\sqrt{8^2-4^2}
    $

    $\displaystyle
    c=\sqrt{48}=\;4\sqrt{3}
    $


    $\displaystyle
    C=180-(90+30)=60
    $
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  3. #3
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    where did 90 come from?

    i get everything else.
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  4. #4
    MHF Contributor
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    Quote Originally Posted by topaz192 View Post
    where did 90 come from?

    i get everything else.
    90 degrees is the angle whose sine is 1.
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  5. #5
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    Ooooh Ok duh. lol thnks!
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