Find the magnitude and the angle that it makes with the positive x-axis?

shemer77
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Homework Statement


find the magnitude and the angle that it makes with the positive x-axis?
http://imageshack.us/photo/my-images/594/unledzmo.png/


Homework Equations





The Attempt at a Solution


The answer that I have is
F= 179.37 at an angle of 91 degrees. Am I right?
I took F1 and multiplied that by <cos60,sin60>, F2 multiplied that by <cos135,sin135>,F3 multiplied by <cos270,sin270> and then I added up all those vectors. then I used the Pythagorean theorem to get the magnitude then I took the inverse cosign of the x component of the resulting vector divided by the magnitude to get 91 degrees.
 
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That's what I got too. Good work!
 
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