A = (-1, 5)
B = (5, 1)
C = (-4, -2)
a = Segment(A, B)
b = Segment(A, C)
c = Segment(C, B)
D = Midpoint(A, B)
d = Line(C, D)
E = Midpoint(A, C)
e = Line(B, E)
F = Intersect(d, e)