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Homework Help: For the tringle shown what are the :

  1. May 31, 2010 #1
    For the tringle shown what are the :

    my answer :

    a )c = a2 - b2

    81 - 49 = root 32

    b ) tan Q = 2/7 = 0.28

    C ) the angle sin = 9/7 = 1.28

    Attached Files:

  2. jcsd
  3. May 31, 2010 #2


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    First of all, please be a bit more careful with the notation.
    In "c = a2 - b2" I assume that the "2"s mean: square, which is not a priori clear form the context (you could use a^2 or a2 or [itex]a^2[/itex] instead). Then I suppose you want to use the Pythagorean theorem, which is not
    c = a2 - b2
    c2 = a2 - b2.

    Also, 81 - 49 = 32, not root(32) = 5.65685.... What I suppose you wanted to say is, c2 = 81 - 49 = 32, so c = root(32).

    In the picture, you have two angles labeled Q. However, these angles are not equal (that would mean the triangle is isoscles, but having sides of three different lengths that is not the case). So which one do you mean?

    Also, how do you get tan(Q) = 2 / 7? Even if you pick one of the angles Q, I don't see a side of length 2.

    For c) I think you are supposed to invert the tangent function (if tan(Q) = a, then Q = arctan(a)).
    "sin = 9/7" does not mean anything (the sine of what?)
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