I manually created my own version of the Wikipedia math article for barycentric coordinates, which are related to triangle geometry including trilinear coordinates.
I made some edits with distance functions in barycentric coordinates and added geometric scenes. I wonder if there are higher dimensional versions of the centroid, orthocenter, Gergonne point, circumcenter, etc. I typed out the Wikipedia article for the Euler line and adding it as an attachment to this post. I have almost finished typing out the article for triangle center.
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