CK-12 Geometry Concepts

12.5. Reflections http://www.ck12.org

Practice

1. Which letter is a reflection over a vertical line of the letterb?


2. Which letter is a reflection over a horizontal line of the letterb?

Reflect each shape over the given line.

3.y−axis

4.x−axis

5.y= 3

6.x=− 1

Find the line of reflection of the blue triangle (preimage) and the red triangle (image).

7.

8.

9.

Two ReflectionsThe vertices of 4 ABCareA(− 5 , 1 ),B(− 3 , 6 ), andC( 2 , 3 ). Use this information to answer ques-
tions 10-13.

10. Plot 4 ABCon the coordinate plane.


11. Reflect 4 ABCovery=1. Find the coordinates of 4 A′B′C′.


12. Reflect 4 A′B′C′overy=−3. Find the coordinates of 4 A′′B′′C′′.


13. Whatonetransformation would be the same as this double reflection?

Two ReflectionsThe vertices of 4 DEFareD( 6 ,− 2 ),E( 8 ,− 4 ), andF( 3 ,− 7 ). Use this information to answer
questions 14-17.

14. Plot 4 DEFon the coordinate plane.


15. Reflect 4 DEFoverx=2. Find the coordinates of 4 D′E′F′.


16. Reflect 4 D′E′F′overx=−4. Find the coordinates of 4 D′′E′′F′′.


17. Whatonetransformation would be the same as this double reflection?

Two ReflectionsThe vertices of 4 GHIareG( 1 , 1 ),H( 5 , 1 ), andI( 5 , 4 ). Use this information to answer questions
18-21.

18. Plot 4 GHIon the coordinate plane.


19. Reflect 4 GHIover thex−axis. Find the coordinates of 4 G′H′I′.


20. Reflect 4 G′H′I′over they−axis. Find the coordinates of 4 G′′H′′I′′.


21. Whatonetransformation would be the same as this double reflection?