# Direction of the resultant displacement Math help

Problem: A disoriented physics professor drives a distance 3.15km north, then a distance 2.50 km west, and then a distance 1.30km south. Find the direction of the resultant displacement, using the method of components.

So I have done this problem over and over and I keep getting -36.5 degrees west of north. But on Mastering Physics it keeps stating my answer is wrong.

What I did was calculate $\arctan((3.15−1.3)/(−2.5))$ to get the direction of the resultant am I wrong to compute what I wrote before?

Be careful with your angle directions and negative signs. After taking the absolute value, you should get an angle of: $$\arctan\left( \dfrac{3.15 - 1.30}{2.50} \right) \approx 36.5^\circ \text{ North of West} = 53.5^\circ \text{ West of North}$$