Exploring the Nine-Point Circle
2015-09-02 11:58
This applet demonstrates the geometric construction of the Nine-Point Circle of a triangle. It shows how to locate the nine key points: midpoints of sides, feet of altitudes, and midpoints of segments from vertices to the orthocenter. Using lines, orthogonal lines, and circles, it visually proves these points lie on a single circle, illustrating fundamental triangle properties.
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