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Math Help - How much is alpha?

  1. #1
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    How much is alpha?

    Hello !

    We have a square - find alpha ?
    Last edited by yehoram; June 19th 2011 at 04:34 AM.
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  2. #2
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    Re: How much is alpha?

    There is not enough information to answer.
    There must be more given. What else do you know?
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  3. #3
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    Re: How much is alpha?

    Quote Originally Posted by Plato View Post
    There is not enough information to answer.
    There must be more given. What else do you know?
    Sorry !

    This is a square !
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  4. #4
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    Re: How much is alpha?

    Rotate triangle AEB about B, until A rests on C.
    Label the new position of "E" as "G".
    Draw a line from E to G.
    Angle EBG is 90 degrees.
    Angles BEG and BGE are 45 degrees.
    Use Pythagoras' Theorem to calculate |EG|

    Triangle ECG now has all 3 sides (if you let |AE|=1, |EB|=2, |EC|=3)
    and you rearrange the law of cosines to calculate "alpha-45" degrees
    and therefore "alpha".
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  5. #5
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    Re: How much is alpha?

    Quote Originally Posted by Archie Meade View Post
    Rotate triangle AEB about B, until A rests on C.
    Label the new position of "E" as "G".
    Draw a line from E to G.
    Angle EBG is 90 degrees.
    Angles BEG and BGE are 45 degrees.
    Use Pythagoras' Theorem to calculate |EG|

    Triangle ECG now has all 3 sides (if you let |AE|=1, |EB|=2, |EC|=3)
    and you rearrange the law of cosines to calculate "alpha-45" degrees
    and therefore "alpha".
    Thank you !

    You're a genius ! God blesse you !
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