Look to the left hand side and click on the T at the bottom of the tool bar. Click on Incircle. Place curser on the page and left click mouse to create first point. Drag the line to create the second point and left click mouse. You have now constructed a line. Move curser up/down/left/right to create the third vertex of the triangle. You should now see three vertices and a hot pink circle in the center of the triangle. Notice that there are also three dashed line coming from the incenter, these lines represent the radius of the circle. As you animate a vertex, notice how the radii, and area alter as the area nd overall size and shape of the triangle change. You did a wonderful job constructing your incircle!