Respuesta :

lolgal555
It looks like for this one you just need to use the midpoint formula for (2a,0) and (0,-4b).
To do this, just use the midpoint formula:
{ (x1+x2)/2 , (y1+y2)/2 }
So 2a+0/2 = a,
and 0-4b= -2b.
So the answer is the second one, (a,-2b)