Education Technology

Traveling Shapes - Motion Geometry

Published on 06/09/2008

Activity Overview

In this activity, students describe how to move a shape from one place to another in a plane. They learn about translations, rotations, and line reflections.

Before the Activity

  • Start the Geoboard App and format it
  • See the attached PDF file for detailed instructions for this activity
  • Print pages 133 - 144 from the attached PDF file for your class
  • During the Activity

    Distribute the pages to the class.

    Follow the Activity procedures:

  • Construct a triangle ABC
  • Perform a translation called slide and move the triangle first 6 units to the right and then 3 units upwards
  • Observe that the translation notation is given as (6,3)
  • Observe that the translation can also be represented with a directed slide arrow and the coordinates of its final position is given by the amount of horizontal and vertical change between the first and the final position (6,3)
  • Construct other shapes and move the shape according to the directed slide arrow and draw its final position
  • Examine the shapes, draw the slide arrow, and give the coordinates for each translation

  • Observe that the triangle can also be transformed by rotating about point A through any angle
  • Rotate the triangle about point A clockwise 90 degrees, 180 degrees, 270 degrees, and 360 degrees
  • Rotate the triangle counterclockwise 90 degrees and notice that this is the same as rotating it clockwise 270 degrees
  • Try to rotate about point B, 180 degrees, and observe this cannot be done
  • Rotate each shape through the given angle about the given point and sketch the diagram of the rotated position

  • Construct a square ABCD and flip it 2 units about a line IJ
  • Observe that the square is 2 units from line IJ on the other side
  • Flip each shape about the given line and then sketch a diagram of the final reflection image
  • After the Activity

    Review student results:

  • As a class, discuss questions that appeared to be more challenging
  • Re-teach concepts as necessary