A particle's trajectory is defined as x = (1/2t^3 - 2t^2) m and y = (1/2t^2 - 2t)m where t is in s. What is the particle's direction of motion, measured from the x axis, at t=0 and t= 3.5, measured in degrees counterclockwise from the x axis. I started out by plugging in t = 0 and t = 3.5 to the equations given. I then attemped to take arctan(y/x) in both cases to find the direction of motion. my answers for these, 0 degrees and 15.9 degrees respectively, both came back as wrong. Any clues as to what I am doing wrong/how to do it right?