The Braikenridge-Maclaurin theorem is the converse of Pascal's theorem, which states that if the three pairs of opposite sides of (an irregular)
hexagon meet at three collinear
points, then the six vertices lie on a conic, which may degenerate into a pair of
lines (Coxeter and Greitzer 1967, p. 76).
Coxeter, H. S. M. Projective Geometry, 2nd ed. New York: Springer-Verlag, p. 85, 1987.Coxeter,
H. S. M. and Greitzer, S. L. Geometry
Revisited. Washington, DC: Math. Assoc. Amer., p. 76, 1967.
