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Math Help - Help finding sides with other angles of other triangles nearby

  1. #1
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    Help finding sides with other angles of other triangles nearby


    I have to find side 'R'
    L = 6.10 meters, theta = 36.9 degrees, and phi = 53.1 degrees.

    I don't see any way I can attempt this, I'm very rusty with my trig. We have a known side and a right angle, but I don't see how I can make any other angles (since we only have one side I'm assuming I need to get an angle somewhere
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  2. #2
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    Re: Help finding sides with other angles of other triangles nearby

    Quote Originally Posted by PhizKid View Post

    I have to find side 'R'
    L = 6.10 meters, theta = 36.9 degrees, and phi = 53.1 degrees.

    I don't see any way I can attempt this, I'm very rusty with my trig. We have a known side and a right angle, but I don't see how I can make any other angles (since we only have one side I'm assuming I need to get an angle somewhere
    1. I've modified your sketch a little bit (see attachment

    2. According to the definition of the Sine function in a right triangle you'll get:

    \frac RL = \sin(90^\circ - \theta)

    3. Since L and \theta are known you can determine R.
    Attached Thumbnails Attached Thumbnails Help finding sides with other angles of other triangles nearby-winklfinden.png  
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  3. #3
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    Re: Help finding sides with other angles of other triangles nearby

    \frac RL = \sin(90^\circ - \theta)

    Sorry but this line should read:

    \frac RL = \sin(90^\circ - \phi)
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