Awatermelon seed has the following coordinates x -32 m y

Question

Problem: A watermelon seed has the following coordinates: x = -3.2 m, y = 6.9 m, and z = 0 m.

Part A: What is an angle relative to the positive direction of the x axis?

I need help to solve the above problem and put the angles in the range (-180°, 180°].