See the attached PDF file for detailed instructions for this activity

Print pages 49 - 52 from the attached PDF file for your class

During the Activity

Distribute the pages to the class.

Follow the Activity procedures:

Translation:

Construct an asymmetrical polygon

Draw a line to the right of the polygon

Reflect the polygon across the line

Draw a line to the right of the second polygon, and parallel to the first line

Reflect the second polygon across the line

Identify that when an image is reflected over two parallel lines, the transformation is a translation

Measure the distance between the parallel lines

Measure the distance between a vertex of the original polygon (pre-image) and its corresponding vertex in the final polygon (image)

Measure the distance between one other vertex and its corresponding vertex in the third polygon

Observe that the distance between the parallel lines is half the distance of the image and pre-image

Rotation:

Draw and label a line CD

Construct a point A on line CD and draw a line through A

Mark a point B on the line through A

Construct an asymmetrical polygon in the interior of angle DAB and reflect it across line AB

Reflect the new polygon over line AC

Identify that when an image is reflected over two intersecting lines, the transformation is a rotation

Measure angle BAC

Measure the angle between the corresponding parts of the pre-image and image

Note that the angle from the pre-image to image is twice the angle of rotation

Drag line AC to change the angle between the two intersecting lines

Identify that the relationship between the angle from the pre-image to image and the angle of rotation, does not hold true for an obtuse angle because the angle is being read from the other direction

After the Activity

Review student results:

As a class, discuss questions that appeared to be more challenging