CK-12 Geometry Concepts

http://www.ck12.org Chapter 12. Rigid Transformations

• Rotation


• Center of Rotation


• Rotation of 180◦


• Rotation of 90◦


• Rotation of 270◦


• Composition (of transformations)


• Glide Reflection


• Reflections over Parallel Lines Theorem


• Reflection over the Axes Theorem


• Reflection over Intersecting Lines Theorem


• Tessellation

Chapter Review

Match the description with its rule.

1. Reflection over they−axis - A.( 2 a−x,y)


2. Reflection over thex−axis - B.(−y,−x)


3. Reflection overx=a- C.(−x,y)


4. Reflection overy=b- D.(−y,x)


5. Reflection overy=x- E.(x,−y)


6. Reflection overy=−x- F.(x, 2 b−y)


7. Rotation of 180◦- G.(x,y)


8. Rotation of 90◦- H.(−x,−y)


9. Rotation of 270◦- I.(y,−x)


10. Rotation of 360◦- J.(y,x)

Texas Instruments Resources

In the CK-12 Texas Instruments Geometry FlexBook, there are graphing calculator activities designed to
supplement the objectives for some of the lessons in this chapter. See