**ROTATIONS**

Nash, Susan Lake View High School

1-312-880-8140

**OBJECTIVES**
The student will:
1. Define rotation as the composite of two reflections over intersecting lines.
2. Identify rotation images of a figure.
3. Recognize and apply the properties of rotation.
**EQUIPMENT AND MATERIALS**
Rotogram
Overhead projector
Markers for overhead
Transparencies of figures showing reflection, translation, and
rotation.
**RECOMMENDED STRATEGIES**
Demonstrate and review concept and properties of reflection and translation. a)
There is a one-to-one correspondence between points in a plane and their reflection
through a given line. b) Reflections of a set of points through a line preserves co-
linearity, distance, and angle measure. c) Line reflection changes the orientation of
a figure. d) Translation preserves orientation of a figure.
Introduce rotation as a composite of two reflections across intersecting lines.
Show this using transparencies, rotogram, coins, and other objects available to you.
Emphasize that since rotations are composites of reflections; the properties are
similar to reflections and translations.
Provide additional opportunities for reinforcement of concepts using worksheets.

Return to Mathematics Index