Interesting Property of Orthocenter

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Looks Cute, but nothing particularly special about this.
But what if the chosen point is the orthocenter?
Why does this happen?[br][br]Quick answer - the law of sines.[br]A more detailed geometric proof can be found here https://www.geogebra.org/m/kYWnCxtZ[br]For further reading - look up Johnson circles
– Esther Gruenhut

Information: Interesting Property of Orthocenter