In order to answer this, we need to remember the trig values of benchmark angles (π/6 , π/4 , and π/3 in all 4 Quadrants), and we need to remember the coordinate plane definitions of sine and cosine for a circle of radius r instead of 1.
For our circle of radius 4, the coordinates of the point of intersection with Θ's terminal ray are (4cosΘ , 4sinΘ).
Since Θ = - π/3 , x = 2 and y = - 2√3.