For triangles, a circle {nine-point circle} can pass through side midpoints, feet of perpendiculars to sides, and midpoints of line segments between orthocenter and triangle vertices. Nine-point circle center is equidistant to orthocenter and circumcenter.
Mathematical Sciences>Geometry>Plane>Polygon>Kinds>Triangle
3-Geometry-Plane-Polygon-Kinds-Triangle
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Date Modified: 2022.0224