CK12 - Geometry

10. Can a rotationbe describedin termsof reflections?Justifyyour answer.

Answers

1.

2.

3.

4.

5. 
   

   Reflectionaboutthe -axis

   
   


6. 
   


7. 
   

   This is a dilation.

   
   


8. 
   

   No, we can see that eachside of the largertriangleis twiceas long as the correspondingside in the
   original,so this is not lengthpreserving.

   
   


9. 
   

   Yes, a rotationaboutthe originis the sameas two reflectionsdoneconsecutively, one acrossthe

   
   

-axisand then one acrossthe -axis.For a ; rotation,the rule for transformingcoordinatesis

. Now, supposepoint is reflectedtwice,first acrossthe -axis,and then across