Click on the link below to access eTool
Use this eTool to demonstrate the Triangle Angle Sum Theorem.
1. Click the colored points and drag to change the angles.
NOTE: The measurements for each angle are shown at the left panel.
![](https://media.screensteps.com/image_assets/assets/002/255/907/original/1aea2d1c-07b3-4832-81de-e9d559e3aaab.png)
2. Click the circle at left on line 4 to show wich angles are the same.
![](https://media.screensteps.com/image_assets/assets/002/255/909/original/3ad11699-813e-4cee-a7b6-0308fb611d1a.png)