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Trigonometry help, please!!!?

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I need to solve a triangle using trigonometric functions...I've only been given an angle and the length of the side opposite the angle, How do I find the side length adjacent to the angle and the length of the hypotenuse?

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  1. sine(angle) = opposite/hypotenuse


  2. You mensions "hypotenuse",so the triangle ABC must be a rt.<

    triangle. Let C=90*,A and its opposite side a are known,then angle

    B can be found : B=180*-C-A=180*-90*-A=

    90*-A.

    Since tanB=b/a

    =>b=a* tan(90*-A) (where b is the side opposite to B)

    =>b=a*cotA (b can be worked out for a,A are given)

    c is the hypotenuse which can be found by

    a/c=sinA or

    c=a/sinA

  3. GIVEN --

    Angle and length of side opposite the angle

    REQ'D --

    Length of side adjacent to the angle

    Length of the hypotenuse

    Let

    A = value of the angle given

    a = length of the side opposite the angle

    b = length of side adjacent to the angle

    c = hypotenuse

    SOLUTION:

    tan A = (a/b), hence

    b = a/(tan A)

    For the length of the hypotenuse, there are two ways to solve this. First solution,

    sin A = (a/c)

    c = a/(sin A)

    OR, the second solution to determine "c" is to simply use the Pythagorean theorem. Since sides "a" and "b" are known, then

    c = sqrt(a^2 + b^2)

    Hope this helps.


  4. You have more than you think.  You mentioned the hypotenuse.  So you have a second angle as well, a right angle.  With two angles you can calculate the third since all triangles have 180°.  Then use the Law of Sines to get the second side and the Pythagorean Theorem to get the third side.

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