Rotation Around a Point A Rotation is A

Rotation Around a Point

A Rotation is… • A rotation is a transformation that turns a figure around a fixed point called the center of rotation. • A rotation is clockwise if its direction is the same as that of a clock hand. • A rotation in the other direction is called counterclockwise. • A complete rotation is 360˚.

A Ferris wheel makes a 90˚ rotation with ¼ turn.

Describe the Rotation in 2 ways. 120˚ Counter Clockwise 240˚ Clockwise

Describe the Rotation in 2 ways. 55˚ Clockwise 305˚ Counter Clockwise

Describe the Rotation in 2 ways. 175˚ Clockwise 185˚ Counter Clockwise

Describe the Rotation in 2 ways. 165˚ Counter Clockwise 195˚ Clockwise

Estimate the angle and direction of the rotation. About 85˚ Counter Clockwise

Estimate the angle and direction of the rotation. About 60˚ Counter Clockwise

Estimate the angle and direction of the rotation. About 140˚ Clockwise

Rotation Activity

Rotate a figure 180˚clockwise about the origin in the coordinate grid: 1. Sketch original figure on the graph: K(-6, 2) L (-2, 6) M (6, 6) and O (0, 1) 2. Estimate where the new figure K will end up. 3. Draw the new figure. 4. Write down the new ordered pairs. K’ (6, -2) L’ (2, -6) M (-6, -6) O (0, -1) M’ 5. What do you notice about the original ordered pairs and the new ordered pairs? L M O O’ K’ L’

• When you rotate a figure 180˚, does it matter whether you rotate clockwise or counterclockwise? • Compare K to K’, L to L’, and M to M’. What do you notice about each angle pair? • What effect do rotations have on angles? • What effect do rotations have on side lengths? L K M O O’ M’ K’ L’