Varignon's theorem
- Author:
- Chris Sangwin
- Topic:
- Geometry
Varignon's theorem
Take any quadrilateral in the plane. The midpoints of the sides of an arbitrary quadrilateral form a parallelogram.
If the quadrangle is convex or reentrant, i.e. not a crossing quadrangle, then the area of the parallelogram is half the area of the quadrangle.