Juan decided to test what would happen if he rotated an angle.  

1. He copied the angle at right on tracing paper and rotated it $180^\circ$ about its vertex. What type of angle pair did he create? What is the relationship of these angles?

   Answer (a):

   He created a vertical angle pair. The angles have equal measures.

   

2. Juan then rotated the same angle $180^\circ$ through a different point (see the diagram at right). On your paper, draw Juan’s angle and the rotated image. Describe the overall shape formed by the two angles.

   Hint (b):

   They form a letter. Which one?