Answer:
Rearrange equation y = -3√3 x , y/x = -3√3 /1, ( x, y) = ( 1, -3√3)
The radius r is the hypotenuse of the right angle triangle r = √(x2)+(y2) = √( 12+ (-3√3)2 = √ 1+ 9(3) = √28 = 2√7 , and θ = tan-1( y/x) = tan-1( -3√3 / 1) = atan -3√3 or θ = atan( 1/-3√3) + 2πn = -atan3√3 + 2πn where n = number of 2π rotations
In the interval ( 2π, 4π) , θ = - atan( 3√3) + 2π(1) = - atan( 3√3) + 2π
or θ = - atan( 3√3) + 2π(2) = - atan( 3√3) + 4π
( r, θ ) = ( 2√7 , -atan 3√3 + 2π) , ( 2√7, 4.9 rad)
or if r is rotated counterclockwise 180°, = ( -2√7, -atan 3√3 + π) = ( -2√7, 1.76 rad)
in degrees θ = 4.9 rad ( 180 °/ π rad) = 280°, ( r, θ) = ( 2√7, 280º)
in degrees θ = 1.76 rad( 180°/ π rad) = 100º, ( r, θ) = ( -2√7, 100º)