Here is a line that has been dilated by a scale factor of r. You can change the center of dilation, the scale factor, and even the pre-image of the line. What do you notice about the pre-image and the image?
G.SRT.1 Verify experimentally the properties of dilations given by a center and a scale factor. a. A dilation takes a line not passing through the center of the dilation to a parallel line, and leaves a line passing through the center unchanged.