Reflections

Transformations - Reflections

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LO:​ I can reflect an image or a point over any given line

By MAURISA LEE VAN AS

Multiple Choice

A reflection....

• Changes the size of the shape

• Is a mirror image of the pre-image

• Takes place by sliding the shape on the coordinate plane

• Is when you flex

Reflection about the x-axis

Reflection about the y-axis

Multiple Choice

Which answer shows a reflection across the x-axis?

• A

• B

• C

• D

Multiple Choice

Which answer shows a reflection across the y-axis?

• A

• B

• C

• D

Reflection over the line y=x​

​Look at the ordered pairs. Compare that of the pre-image to the image. What do you notice?

Rule for reflecting over y = x

​Switch x and y values

Example (3 , 4) will become (4, 3)

Multiple Choice

What would the new coordinates of the BLUE point be if it were reflected over y=x

• (5,-2)

• (2,8)

• (5,2)

• (-5,2)

Reflection over the line y=-x​

​Look at the ordered pairs. Compare that of the pre-image to the image. What do you notice?

Rule for reflecting over y = -x

​Switch x and y values and change the sign of both

Example (3 , 4) will become (-4, -3)

Multiple Choice

What would the coordinates of point Q be, if the image were to be reflected over the line y = -x?

• (-3,-6)

• (-3,6)

• (-6,-3)

• (3,-6)

The line of Reflection

​The line of reflection is the line over which the image is mirrored

Different lines of reflection

​Reflect over the line x = -2

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What do you notice?​

Open Ended

What would the coordinates of R' be if the image were to be reflected about the line y=1?

Poll

How do you feel about Reflections?

• I am good to go! I understand completely :)

• I mostly understand but feel the need for more practice

• I understand a little

• I don't understand it at all :(