Respuesta :

M1=[(4a+0)/2 ,(4b+0)/2] = (2a, 2b)
M2=[(4c+4d)/2 ,(4b+0)/2] = [2(c+d) , 2b]

answer
coordinate points (x,y) :
(2a, 2b) , [2(c+d) , 2b]