GeoGebra Klaslokaal

## Introduction

You can build up a construction or a froof stepwise using cascading chekboxes. Checking the first one makes the next visible etc. Following applet illustrates this in the construction of the circumcercle of a triangle.

## How do you do this?

• Checkbox: In the toolbar you can find the Checkbox tool. Select the tool and click four times in the Graphics to create four checkboxes (check1, check2, check3 and check4)
• Condition to show checkbox 2: - Rightclick on check2, open its Properties and select the tab Advanced. - Type check1 in the textfield Condition to Show Object.
• Condition to show checkbox 3 and 4: - The condition to show checkbox 3 becomes check1 && check2. - The condition to show checkbox 4 will be check1 && check2 && check3.
• Button: You can create a reset button to uncheck all the checkboxes with the scripting commands ```SetValue(check1,false) SetValue(check2,false) SetValue(check3,false) SetValue(check4,false)```
• Construction Make your geometrical construction. Refer to one of the checkboxes in the tab Advanced of the objects to show the construction stepwise. Eventually you can add some texts and show them conditionally to.