Hexagon circle) with vertices given by the six intersections of the edges of a triangle and the three lines that are parallel to the edges that pass through its symmedian point. If the successive sides of a cyclic hexagon are "a", "b", "c", "d", "e", "f", then the three main diagonals intersect in a single point if and only if . If, for each side of a cyclic hexagon, the adjacent sides are extended to their intersection, forming a triangle exterior to the given side, then the segments connecting the circumcenters of opposite triangles are concurrent. If a hexagon has vertices
Magic hexagon Magic hexagon A magic hexagon of order "n" is an arrangement of numbers in a centered hexagonal pattern with "n" cells on each edge, in such a way that the numbers in each row, in all three directions, sum to the same magic constant "M". A normal magic hexagon contains the consecutive integers from 1 to 3"n" − 3"n" + 1. It turns out that normal magic hexagons exist only for "n" = 1 (which is trivial, as it is composed of only 1 hexagon) and "n" = 3. Moreover, the solution of order 3 is essentially unique. Meng also