GeoGebra Lab 15

1. Turn off grids and coordinate axes.
2. Draw a triangle.
3. Select the Angle Bisector tool. Use it to create an angle bisector by clicking on three vertices of the triangle. Repeat the process to create angle bisectors of the other two angles.
4. Create a point where the three lines are concurrent by using the Intersect tool. This point of concurrency is the incenter of the triangle.
5. To create an inscribed circle, you will need to create one more line to define where the inscribed circle touches a side. Create a line perpendicular to one side of the triangle that goes through the incenter.
6. Create a point where the perpendicular line intersects the side of the triangle.
7. Draw the inscribed circle using the circle tool with the center of the circle at the incenter, and the radius of the circle that goes to the intersection point created in the last step.
8. Move the triangle to see that the circle remains inscribed.