X(2)    CENTROID

The centroid, labeled 2, is the point 
of concurrence of the medians, AA', 
BB', CC'.

Sketch contributed by Michael Stairs,
January 2018.

Drag A, B, C.

2

A = (1.9286418822410174, 2.510076763957574)
B = (-1.52, -0.1)
C = (3.9684949783033603, -0.006149210825914048)
f = Segment(B, A)
g = Segment(A, C)
h = Segment(C, B)
i = AngularBisector(B, C, A)
j = AngularBisector(C, B, A)
C' = Midpoint(f)
B' = Midpoint(g)
A' = Midpoint(h)
k = Segment(C', C)
l = Segment(B, B')
m = Segment(A', A)
D = Intersect(k, l)