- Jack D. Gittinger
Step 1. Construct One the GeoGebra page you will see four geometric objects: 1. Point A 2. Point B 3. Point C 4. Line BC On the Tool Bar there is a PARALLEL LINE tool.Click on the PARALLEL LINE tool to select it. Notice the instructions for this GeoGebra tool: SELECT POINT AND PARALLEL LINE. Click first on Point A and then click on Line BC. This will create a new, parallel line. But just what is a parallel line? Step 2. Experiment Use the MOVE tool to experiment by moving Points A, B, or C. Move the two lines as well. Make observations. If needed, use the ZOOM IN or ZOOM OUT tools to change your view. Step 3. New Construction Use the DELETE OBJECT tool to click on the points and lines on the GeoGebra page and delete them. Now use the NEW POINT tool, the LINE THROUGH TWO POINTS tool, and the PARALLEL LINE tool to create your own parallel lines and again experiment by moving points or lines. Step 4. Conclusions So just what is a parallel line? Share your conclusions with your teacher.