9 3 Rotations I can draw rotations in

9. 3: Rotations I can draw rotations in the coordinate plane.

If the images to the right describe a Rotation, in your own words, define rotation:

Vocabulary! Center of Rotation Angle of Rotation • a rotation or turn moves every point in a preimage through an angle and direction about a fixed point • fixed point is called the center of rotation • Corresponding points in an image and preimage are equidistant from the center of rotation • if the point is on the center of rotation then image & preimage are the same point • otherwise, the angle of rotation is the angle formed by the preimage, center of rotation, and image

Vocabulary! • clockwise (to the right) Direction of • Counterclockwise (to the left) Rotation • Assume rotations are counterclockwise unless otherwise told

Rotations on a Coordinate Plane 90˚ Rotation 180˚ Rotation 270˚ Rotation

Example 1: Triangle DEF has vertices D(– 2, – 1), E(– 1, 1), and F(1, – 1). Graph ΔDEF and its image after a rotation of 270˚ about the origin?

Example 2: Hexagon DGJTSR is shown below. What is the image of point T after a 90 counterclockwise rotation about the origin?

Example 3: Triangle PQR is shown below. What is the image of point Q after a 180° counterclockwise rotation about the origin?

Example 4: Find the image that represents the rotation of the polygon about the origin. Then graph the polygon and its image.

Example 4: Find the image that represents the rotation of the polygon about the origin. Then graph the polygon and its image.