In the plane of any triangle ABC, let
D = the midpoint of side BC,
G = foot on BC of altitude from A,
J = midpoint of segment AX, (X, the orthocenter, is where the altitudes AG, BH, CI meet.)
As you see in the sketch, a circle passes through all nine of the points D,E,F,G,H,I,J,K,L. It is the |

Triangle Centers

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