Varignon's theorem

== English == === Etymology === Named after French mathematician Pierre Varignon. === Proper noun === Varignon's theorem (geometry) A statement in Euclidean geometry that deals with the construction of a particular parallelogram (the Varignon parallelogram) from an arbitrary quadrilateral. (mechanics) A theorem stating that the torque of a resultant of two concurrent forces about any point is equal to the algebraic sum of the torques of its components about the same point.