Close but not quite.... cos adding 3+i onto the vector 2z should move it upwards by i and right by 3, so logically the centre of the circle should shift by the same amount
Or convert into parametrics question:
Let P=z=x+iy so x^2+y^2=k^2 (x,y,X,Y are real)
Let Q=X+iY such that Q=2z+3+i...