Geometric Construction and Demonstration of the 9-Point Circle
2011-12-10 15:53
This applet demonstrates the geometric construction of the Nine-Point Circle of a triangle. The nine-point circle passes through the midpoints of the three sides, the feet of the three altitudes, and the midpoints of the segments from the orthocenter to the vertices. Using GeoGebra commands such as Polygon, Midpoint, and OrthogonalLine, it dynamically illustrates the concyclic property of these ni
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