Based on the given original and dilated points, you can notice that the dilation is:
(x,y) => (1/3 x , 1/3 y)
This can be verified with any point of the figure, for example:
C(6,-3) => C'(1/3 (6) , 1/3 (-3)) = C'(2 , -1)
Hence, the answer is:
(1/3 x , 1/3 y)