Frenzied flipping

Flip in GeoGebra

Learn the conventional notation for image points.

1. Choose the point tool.
2. Click on the grid at the location (1, 2). Notice that this point is labelled A.
3. Predict the new coordinates if A was reflected in the x-axis. Then check your answer:
   • Click on the reflect tool.
   • Click on A.
   • Click on the x-axis.
   • Notice that the reflected point is labelled A’ (often pronounced ‘A prime’). This is a common way to label points that have been transformed in some way.
4. Using the move tool, drag point A and notice how the position of A’ changes.
5. Change back to the point tool and click to draw another point somewhere on the plane.
6. Predict the coordinates of B’ if B is reflected in the y-axis.
7. Use the reflect tool to check your answer.