The displacement vectors A and B shown in figure 3-17 both have magnitude 2m. Find graphically (a) A + B, (b)?

The displacement vectors A and B shown in figure 3-17 both have magnitude 2m. Find graphically (a) A + B, (b) A - B, (c) B - A http://imageshack.us/photo/my-images/515/photouw.jpg/ The link above contains the picture for the problem. Please help me out here!