image.
[C, CN, T, V]
Translations, reflections and rotations are new topics to Grade 5
students.
It may be helpful for students to create a graphic organizer such
as a Venn diagram or a foldable to list the attributes of the three
transformations as they are introduced. This may later help them
identify the transformation which resulted in a given image. When
labelling a 2-D shape and its transformed image, prime notation should
be used. If the original shape is labelled ABCD, for example, its image
will be A B C D .
To introduce translations, teachers could draw a 2-D shape using
grid paper, replicate it and move it to a new location. Generate a
discussion on key words such as horizontal, vertical, diagonal, etc. Note
that the terms up, down and across are equally acceptable. Discuss
the orientation of the shape after a translation. In a translation the
orientation does not change.
Orientation is not the same as direction. This is a common
misunderstanding. Orientation is related to the relative position of the
vertices of a polygon. When orientation changes, vertices of the shape
are in a different order.
Students should then begin performing translations. They could
cut a shape out of an index card, label the vertices, and trace it on a
sheet of paper to create its original position. It can then be translated
to a new location on the paper, traced again and the image labelled.
Students should label the vertices of the shape (e.g., A, B, C, D) and the
corresponding vertices of the reflected image (e.g., A
'
, B
'
, C
'
, D
'
). Be
sure that they do not flip the card over. It might be useful to have them
write TOP on the side of the card that should be visible when tracing
around the shape.
Students should recognize that for a translation:
• the 2-D shape and its image are congruent
• the 2-D shape and its image have the same orientation (i.e., if we
go around the object ABCD in a clockwise direction, we should be
able to also go around its translated image, A
'
B
'
C
'
D
'
, in a clockwise
direction).
Teachers could then model drawing 2-D shapes such as squares,
rectangles and triangles and translating them to a new location. Students
should draw and translate simple 2-D shapes. It might be helpful to ask
students to use grid paper for their beginning translations to help them
ensure the move is the correct number of units up or down, left or right.
5SS7.1 Translate a given 2-D
shape horizontally, vertically
or diagonally, and describe the
position and orientation of the
image.
5SS7.2 Draw a 2-D shape,
translate the shape, and record
the translation by describing the
direction and magnitude of the
movement.
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