Statics Question: Finding resultant force and orientation

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SUMMARY

The discussion focuses on calculating the resultant force (FR) from two forces, F1 = 230 lb and F2 = 395 lb. The magnitude of the resultant force is confirmed as 402 lb. However, the user struggles with determining the correct direction of FR, initially calculating an angle of 11.6 degrees from the x-axis, which is incorrect. The correct approach involves finding the components of both forces and using trigonometric functions to accurately determine the angle of the resultant force measured counterclockwise from the positive x-axis.

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Determine the magnitude of the resultant force FR. Assume that F1 = 230 and F2 = 395
Express your answer to three significant figures and include the appropriate units.

Determine the direction of the resultant force FR , measured counterclockwise from the positive x axis.

I got the magnitude as 402lb which is correct, but I am having trouble finding the direction of the force.

I have the following work below

http://img5.imageshack.us/img5/1954/resultantforce.png

So I get \phi=71.6 degrees

Now the first quadrant has an angle from F1 to the x-axis that measures at 60 degrees. What I did was 71.6-60 degrees = 11.6 degrees and said that was the angle of the resultant force, but this answer is wrong.

Can anyone explain how to find the angle? Should I be subtracting 360 from 11.6 degrees instead since it wants the position counterclockwise?
 
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Why don't you find the components of F1 and F2 and add them to determine the resultant?
 

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