Anticomplementary Triangle

A Triangle $\Delta A'B'C'$ which has a given Triangle $\Delta ABC$ as its Medial Triangle. The Trilinear Coordinates of the anticomplementary triangle are

$$A' = -a^{-1}:b^{-1}:c^{-1}$$

$$B' = a^{-1}:-b^{-1}:c^{-1}$$

$$C' = a^{-1}:b^{-1}:-c^{-1}.$$

See also Medial Triangle