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Incircle of a Polygon

Abstract:: An interactive applet and associated web page that demonstrate the incircle of a polygon - The largest circle the will fit inside a polygon that touches every side. The applet shows a polygon where the user can drag any vertex and change the number of sides. As they do so, the incircle is drawn for that polygon and the radius calculation is updated. Calculation can be turned off for class discussions. The text on the web page gives two formulae for calculating the inradius, depending on the initial givens. Applet can be enlarged to full screen size for use with a classroom projector. This resource is a component of the Math Open Reference Interactive Geometry textbook project at http://www.mathopenref.com.

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Triangle incircle

Abstract:: A web page and interactive applet demonstrating the concept of the incircle of a triangle - the largest circle the will fit inside a triangle. The applet shows a triangle where the user can drag the vertices around. The incircle is continuously adjusted as the user drags the vertices. By experimentation the user can observe that the three sides of the triangle are always tangents to the incircle. The page text explains the definition of the incircle and how to draw it. It describes how the incenter is the center of the incircle of the triangle with a link to that page http://www.mathopenref.com/triangleincircle.html Applet can be enlarged to full screen size for use with a classroom projector. This resource is a component of the Math Open Reference Interactive Geometry textbook project at http://www.mathopenref.com.