Using a slider and a point of dilation as an introduction to dilation
What happens when you change the point of dilation? What happens when you increase the scale factor? What changes? What stays the same? What happens when you decrease the scale factor? What changes? What stays the same? Under what circumstances is the image larger than the preimage? Under what circumstances is the image smaller than the preimage? Same size? Find the ratio of the distance from D to C to the distance from D to C'. Do the same thing with B and B'. Do the same thing with A and A'. What do you notice?