Coordinate Moves

Move LARGE POINTS on the triangle around to see the effect of translation on Lisa’s picture. The original picture has coordinates at the base.

Exploring Translations in the coordinate plane.

Five points are plotted on the coordinate plane below.

  • Using the Pen tool   or the Text tool, label each of its coordinates.​
  • Using the x-axis as the line of reflection, plot the image of each point.​
  • Label the image of each point with its coordinates.​
  • Include a label using a letter. For example, the image of point A should be labeled A’.​

Apply transformations to a line segment.

(A). Rotate segment   in the applet below 90 degrees counterclockwise around center  by moving the slider. The image of  is named C. 

(1). What are the coordinates of C?

(B). Rotate segment   in the applet below 90 degrees counterclockwise around center by moving the slider. The image of  is named D. 

(2). What are the coordinates of D ?

(C). Rotate segment   in the applet below 90 degrees clockwise around by moving the slider. The image of  is named E and the image of  is named F.  

(3). What are the coordinates of E and F ?

(4). Compare the two 90-degree counterclockwise rotations of segment  . What is the same about the images of these rotations? What is different?

(5). Suppose  EF and GH are line segments of the same length. Describe a sequence of transformations that moves  EF to  GH.

The point R has coordinates (3, 2).

  • Without graphing, predict the coordinates of the image of point R if it were reflected using the x–axis as the line of reflection.​
  • Check your answer by finding the image of R on the graph.​
  • Label the image of R as I