GeoGebra
You can use GeoGebra to draw circles. GeoGebra has three built-in tools for drawing circles depending on the information you have about the circle:
- 1.
- If you have information on the center, and a point on the circle, choose Item 4.
- 2.
- If you have information on the center, and the radius of the circle, choose Item 4.
- 3.
- If you have information on three points on the circle, choose Item 3.
GeoGebra Instruction 1
Circle with Given Center and Boundary Point
- 1.
- Open
Algebra ViewandGraphics ViewunderViewinMenu. - 2.
- Click on
Circle with Center through Point.
- 3.
- Click on a chosen point on the
Graphics View. The chosen point will be the center of the circle. - 4.
- Decide the length of the radius of the circle by moving the cursor away or toward the center.
- 5.
- Left-click when you have decided on the length of the radius. The size of the circle should not change when you move the cursor. The circle is now shown in
Graphics View. - 6.
- If you wish to know the length of the radius, click on
Distance or lengthand click on the the point in the center and the point on the circular arc. The length of the radius will now be shown.
The circle will now appear in Graphics View. The equation of the circle will appear in a row in Algebra View as well.
GeoGebra Instruction 2
Circle with Given Center and Radius
- 1.
- Open
Algebra ViewandGraphics ViewunderViewinMenu. - 2.
- Click on
Circle: Center & Radiuswhich is the sixth button on the toolbar and the second tool in the tool list. Click on a chosen point on the
Graphics View. The chosen point will be the center of the circle. - 3.
-
GeoGebrawill now ask you to type in the radius of the circle. Type in the radius that you want. Click onOK.
The circle will now appear in Graphics View. The equation of the circle will appear in a row in Algebra View as well.
Example 1
Draw a circle with a radius of 5 in GeoGebra
You choose to use Circle: Center & Radius to draw the circle. The location of the center on the
Graphics View does not matter.
GeoGebra Instruction 3
Circle Through Three Points
- 1.
- Open
Algebra ViewandGraphics ViewunderViewinMenu. - 2.
- Create the three points that you have been given by clicking on each of their positions.
- 3.
- Click on
Circle through 3 Pointswhich is the sixth button on the toolbar and the fourth tool in the tool list. Click on the three points that you made in the previous step. The order does not matter.
The circle will now appear in Graphics View. The equation of the circle will appear in a row in Algebra View as well.