Analyze Reflections

How does a reflection affect the properties of a two-dimensional figure?

Select all that may apply.

• The preimage and image are not congruent.

• The orientation of the figure and the orientation of the vertices stays the same.

• The orientation of the figure and the orientation of the vertices changed.

• The preimage and image are congruent.

• The figures are flipped and mirror images of one another.

Tags

CCSS.8.G.A.3

CCSS.HSG.CO.A.5

What do you notice about the corresponding coordinates of the preimage and image after a reflection across the x-axis?

Tags

CCSS.8.G.A.3

CCSS.HSG.CO.A.5

Jorge said the y-values would stay the same when you reflect a preimage across the line y=5 since the y-values stay the same when you reflect a preimage across the y-axis. Is Jorge correct? Explain.

• Jorge is correct. y = 5 is a vertical like the y-axis and would cause the y-values to stay the same.

• Jorge is incorrect. y = 5 is a horizontal that would reflect over. The x-axis is also horizontal which changes the y-values.

Tags

CCSS.8.G.A.3

CCSS.HSG.CO.A.5

• yes

• no

Tags

CCSS.8.G.A.3

CCSS.HSG.CO.A.5

Describe the reflection of figure EFGH.

• Reflected over the x-axis

• Reflected over the line y = 4

• Reflected over the y-axis

• Reflected over the line x = 4

Tags

CCSS.8.G.A.3

CCSS.HSG.CO.A.5

Graph the line x = -1

Identify the points of the trapezoid

• (2, 8)

• A

• (1, 3)

• B

• (6, 8)

• D

• (8, 3)

• C

Tags

CCSS.5.G.A.1

Identify the points of the trapezoid after its been reflected across the y-axis.

What is the image coordinates?

A' - (a)  

B' - (b)  

C' - (c)  

D' - (d)  

• (-2, 8)
• (-6, 8)
• (-8, 3)
• (-1, 3)
• (2,-8)
• (6,-8)
• (8, 3)
• (-1, -3)

Tags

CCSS.8.G.A.3

CCSS.HSG.CO.A.5

Is the triangle A'B'C' a reflection of triangle ABC across the line? Explain.

• Yes, because the figures are mirror images of one another.

• No, because the orientation of figure and vertices are the same. That is a characteristic of translation.

Tags

CCSS.8.G.A.3

CCSS.HSG.CO.A.5

Your friend gives you the graph of quadrilateral ABCD and its image, quadrilateral A'B'C'D'.

What reflection produces this image?

• y = 1

• y-axis

• x = 1

• x-axis

Tags

CCSS.8.G.A.3

CCSS.HSG.CO.A.5