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    I have been working on this problem for about an hour and can't seem to get a solution. Can anyone help?

    Two forces P and Q have magnitudes 3N and 6N respectively and act at point O. The angle between P and Q is acute. The resultant is R which makes an angle of 20 degrees with Q. Find the angle between P and Q and the magnitude of R.

    All I've done is get the equations:
    3sin(x) = Rsin20
    3cos(x) + 6 = Rcos20

    Some rearranging got me as close as
    Tan20 = sin(x) / cos(x)+2
    But I still can't get a solution.
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    (Original post by Bobrey)
    I have been working on this problem for about an hour and can't seem to get a solution. Can anyone help?

    Two forces P and Q have magnitudes 3N and 6N respectively and act at point O. The angle between P and Q is acute. The resultant is R which makes an angle of 20 degrees with Q. Find the angle between P and Q and the magnitude of R.

    All I've done is get the equations:
    3sin(x) = Rsin20
    3cos(x) + 6 = Rcos20

    Some rearranging got me as close as
    Tan20 = sin(x) / cos(x)+2
    But I still can't get a solution.
    If you multipy up, and then square both sides, you can get a quadratic in cos x
 
 
 
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