1. Reflection on the Coordinate Plane

2. Describe the movement to superimpose one figure over the other
The y-axes is also the line x = 0
The x-axes is also the line y = 0
1. Select the shape
2. From the drop down select Reflect Shape
3. Select the line over which to reflect
A reflection (flip) over the y-axis
(the line X=0)

3. What do you notice about the original and the reflected triangle?
Touch the red triangle. From the drop
down select Show/Hide Vertex Points C C' A' A B' B
What happens to the coordinates of triangle
ABC when it is reflected over the y-axis?

4. Summary: Reflection over the y-axisB' B
A(3,4) A'(-3,4)
B(6,2) B'(-6,2)
C(6,6) C'(-6,6)
(x,y)
(-x,y)

5. Describe the movement to superimpose one figure over the other
The y-axes is also the line x = 0
The x-axes is also the line y = 0
1. Select the shape
2. From the drop down select Reflect Shape
3. Select the line over which to reflect
A reflection (flip) over the x-axis
(the line Y=0)

6. What do you notice about the original and the reflected triangle?
Touch the red triangle. From the drop
down select Show/Hide Vertex Points C A B A' B' C'
Label the image

7. Summary: Reflection over the x-axis
A(3,4) A'(3,-4)
B(6,2) B'(6,-2)
C(6,6) C'(6,-6) A B
(x,y)
(x,-y) B' A' C'

8. B" (____,____) B" Reflect rectangle ABCD over:
Use the Pen Tool to complete the coordinate pairs.
Drag the letters to label each image.
Touch rectangle ABCD and Reflect Shape over a) x = 0 b) y = 0
Reflect rectangle ABCD over:
a) the y-axis b) the x-axis a)
A' (____,____) A' A B
B' (____,____) B' C'
C' (____,____) D C
D' (____,____) D' b)
A" (____,____)
A"
B" (____,____)
B"
C" (____,____)
C"
D" (____,____)
D"

9. Solution B' A' A B C' D' D C
D"
C"
A"
B"

10. B" (____,____) B" Reflect triangle ABC over:
Use the Pen Tool to complete the coordinate pairs.
Drag the letters to label each image.
Touch triangle ABC and Reflect Shape over a) x = 0 b) y = 0
Reflect triangle ABC over:
a) the y-axis b) the x-axis a) A'
A' (____,____)
B' (____,____) B' C'
C' (____,____) C B b)
A" (____,____)
A"
B" (____,____)
B" A
C" (____,____)
C"

11. Solution
A"
C"
B" C B B' C' A A'

12. Describe the reflection
Use Reflect Shape to
check your answer
A reflection over the line y=x