First look at one of the point covered by the black shape, example of which being (2,2).
Next look at where the corrosponding point on the dilated figure is, so keeping with the sample, (10,10).
With this, knowing that both of the shapes are centered around the origin and that they are dilations of each other, do 10/2. to give you 5.
This would be the dilation needed to get the black shape to become the black shape.
Hope that helps.
