1. 11.4 Rotations
1/12/17

2. Rotation
A transformation in which a figure is rotated about a point called the center of rotation
The number of degrees a figure rotates is called the angle of rotation
Rotations can occur clockwise or counterclockwise

3. Example 1 A
Which of these shows a 270° counterclockwise rotation of the figure A? E D B C

4. Performing Rotations
To rotate a figure 180°, draw a 180° angle with its vertex on the center of rotation and its endpoints on each old point and new point.
This example shows a 180° rotation around the origin.

5. Example 2
Rotate the figure 180° about the origin.

6. Performing Rotations
To rotate a figure 90°, draw a 90° angle with its vertex on the center of rotation and its endpoints on each old point and new point.
This example shows a 90° counterclockwise rotation around point L.

7. Example 3
Rotate the figure 90° clockwise around point F. A B C D F E

8. Example 4
The red figure is the original. What series of transformations may have occurred to produce the blue figure?