Exploring symmetry
Task
Create an applet for exploring the symmetry of a picture by reflecting a point A at a symmetry line to create its image A'.
Explore the construction...
Instructions
Learn how to recreate the figure used above to explore the concept of symmetry.
1. | Make sure that you have the picture of the yellow flower saved on your computer before you start with the actual construction. | |
2. | ![]() | Create a new point A. |
3. | ![]() | Construct a line of reflection through two new points by clicking twice into the ![]() |
4. | ![]() | Mirror point A at the line to get its image A’. Hint: First select point A and then the line. |
5. | ![]() | Create a segment between point A and its image A’ by selecting both points. |
6. | ![]() | Turn the trace on for points A and A′.
Hint: Right-click (MacOS: Ctrl-click) on a point and select Show Trace.
Note: Whenever point A is moved, it leaves a trace in the ![]() |
7. | ![]() | Drag point A to draw a trace.
Hint: The menu item Refresh Views in the ![]() |
Try it yourself...
Instructions (continued)
Learn how to recreate the figure used above to explore the concept of symmetry.
8. | ![]() | Insert the image of the yellow flower into the ![]() |
9. | ![]() | Adjust the position of the inserted image using the Move tool. |
10. | ![]() | Set the image as Background Image using tab Basic of the the Settings (![]() |
11. | ![]() | Reduce the Opacity of the image using tab Color of the Settings (![]() |
Hint: After specifying the picture as a background image you can’t select it in the ![]() |