In an equilateral triangle what is the relasionship between the length of a side and the perimeter

Pentagon abcde is dilated according to the rule do,3(x,y) to create the image pentagon a'b'c'd'e', which is shown on the graph. what are the coordinates of point a of the pre-image? a) (-1, 1)b) (-1, 2)c) (-9, 6)d) (-9, 18)