This Instructional Activity is a part of the Lesson 2, Unit 3, Grade 8. Example 4 demonstrates that dilations map rays to rays. It also demonstrates how to use a ruler to dilate with scale factor r = 1/2. Similar to Example 1, before this example, discuss the conjectures students developed about rays. Also, consider getting students started and then asking them to finish with a partner. This example shows that a dilation maps a ray to a ray.