How to calculate resultant vector angle?

[euphtone06]

1. A person walks in a path which consists of four straight lines at different angles and lengths as seen in the attached image. http://img253.imageshack.us/img253/244/problemlt5.gif
The first part of the problem was to find the resultant displacement which was found to be 512.8. The second part asks what is the direction measured from due west, with counterclockwise being in the positive direction of the person's resultant displacement?

The Attempt at a Solution

I am having a hard time understanding what the problem means by measured from due west I found the angle of the typical resultant displacement to be 237.26 degrees but this answer was wrong. Is it simply adding +/- 180 for due west? I am confused

 

[Doc Al]

I am having a hard time understanding what the problem means by measured from due west

For example, if the displacement was due east it would be 180 degrees as measured from due west.

I found the angle of the typical resultant displacement to be 237.26 degrees but this answer was wrong.

What are you measuring your angle with respect to? (From due east, I presume.)

Is it simply adding +/- 180 for due west?

Yes, it's as simple as that. But draw a careful diagram to figure it out.

 

[euphtone06]

Yes I measured the angle from due east so 237.26-180= 57.26 would be my answer from due west?

 

[Doc Al]

Sounds good to me. (I didn't check your original answer though.)