Dilations are when you change the size of a shape by a scale factor. A scale factor greater than 1 increases the size of the shape, and a scale factor between 0 and 1 decreases the size of the shape.
As you click through the three images to the right, you can see how dilations work on the coordinate plane. Sometimes you can dilate using the origin as the center, and other times you can use a point on the shape. Whenever you dilate, each side increases by the scale factor. If you dilate around the center, the value of every coordinate increases by the multiple that is the scale factor. If you dilate around a point on the shape, one coordinate stays the same and the rest change by the scale factor. 


