GeoGebra is an excellent way to let students explore math concepts. GeoGebra is great for grades K – college. When creating elements in a GeoGebra applet you will need to be able to duplicate objects. Tim Brzezinzski, the GeoGebra expert, helps me, Victoria Thompson, and Chris Brownell explore duplicating (and other things) in GeoGebra.
Sign Into GeoGebra
I sign into GeoGebra with my Google Account.
Click on “Profile” on the left hand side to create activities.
Create an Activity
A book is a collection of activities. I am wanting to add an applet to an activity that allows me to duplicate an object.
Create a GeoGebra Applet
In the activity you can add “GeoGebra”
You can select a pre-made applet or you can create a new one.
Choose a Calculator
You will choose which calculator you want to create your applet with. The Graphing math app has the most options.
Use the Move Tool
For me it is important to remember to keep toggling the move tool. This is the first icon, an arrow, in the toolbar. When you select other tools, that tool remains selected. Usually I want to create a line and then move it or do something to it so I have to remember to immediately click on the arrow move tool after each action.
Right Click to Remove Grid
The default is the graphing calculator with the x and y axis. If you’re trying to create an activity where you want to move objects there is a good chance you want to remove the x and y axis. Right click to remove “Axes” and then right click again to remove “Grid.”
I have placed down 3 points and drawn 3 line segments. I want to duplicate this triangle to create a congruent figure. The problem is that I created this as separate objects. I am able to move one of the points around and the line segments stay connected, but it does not act as a it’s own object. It is a compilation of parts.
Use the Polygon Tool
The polygon tool will do this faster… and create an object rather than a collection of parts. Choose the Polygon tool from the toolbar and click on the Polygon tool.
To duplicate the polygon you just created, first click on the move arrow and click on the polygon you just made. Now choose “Rigid polygon” from the tools menu. Click on the polygon you want to duplicate and then immediately click back on the move arrow. This will create a clone of the polygon. Use the move tool to move it into position. On the original polygon, move one of the vertices, it will move also on the clone.
Try Advanced Settings
When adding an applet to a GeoGebra activity, you may want to click on “Advanced Settings” and choose to switch from the classic GeoGebra to the Suite.
Duplicate a Circle
Use the circle tool to create a circle. Select the move arrow to avoid accidentally creating a second circle. Select the compass tool and simply click on the edge of the circle to duplicate the circle. Changing the size of the first circle will automatically adjust the size of the duplicated circle.