9.1e Class Activity: Congruence
The following phrases and words are properties or descriptions of one or more of the transformations we have
studied so far: translation, reflection, and rotation. Determine which type of transformation(s) the statements
describe and write your answer(s) on the line. An example of each type of transformation has been provided
below to assist you.
Create cut-out shapes or smartboard shapes to manipulate.
8
translation
P'
R'
S'
15
Q'
S
Q
P
pre-image
10
Q'
P'
P'
4
R
reflection
across
y-axis
S'
R'
2
5
rotation Q'
about
origin
Flip
6
5
R'
S'
Property/Description
10
15
20
2
4
6
8
10
Type of Transformation(s)
reflection
Slide
translation
Turn
rotation
Image has the same orientation as pre-image.
Translation, rotation
Specified by a figure, a center of rotation, and an angle of rotation.
rotation
Specified by a figure and a line of reflection.
Specified by a figure, a distance, and a direction.
reflection
Segments connecting corresponding vertices of image and pre-image are the same
length.
Corresponding image and pre-image vertices lie on the same circle.
Segments connecting corresponding vertices of image and pre-image are parallel
to each other.
Line of reflection is the perpendicular bisector of all segments connecting
corresponding vertices of the image and pre-image.
Concentric circles
Orientation of the figure does not change.
The slopes of corresponding segments may change.
Corresponding segments in the image and pre-image are the same length.
Corresponding angles in the image and pre-image have the same measure.
Parallel lines in the pre-image remain parallel lines in the image.
37
translation
translation
rotation
translation and reflection
reflection
rotation
translation and rotation
reflection, rotation
translation, reflection, rotation
translation, reflection, rotation
translation, reflection, rotation
2014 University of Utah Middle School Math Project in partnership with the
Utah State Office of Education. Licensed under Creative Commons, cc-by.