Léon Anne's Theorem

Pick a point in the interior of a Quadrilateral which is not a Parallelogram. Join this point to each ofthe four Vertices, then the Locus of points for which the sum of opposite Triangleareas is half the Quadrilateral Area is the line joining the Midpoints and ofthe Diagonals.

References

Honsberger, R. More Mathematical Morsels. Washington, DC: Math. Assoc. Amer., pp. 174-175, 1991.

• Sink (Map)
• Sinusoidal Projection
• Sinusoidal Spiral
• Sinusoidal Spiral Inverse Curve
• Sinusoidal Spiral Pedal Curve
• Sister Celine's Method
• Site Percolation
• Siteswap
• Six-Color Theorem
• Skein Relationship
• Skeleton
• Skeleton Division
• Skew Conic
• Skewes Number
• Skew Field
• Skew Lines
• Skewness
• Skew Polyomino
• Skew Quadrilateral
• Skew Symmetric Matrix
• Sklar's Theorem
• Skolem-Mahler-Lerch Theorem
• Skolem Paradox
• Skolem Sequence
• Slant Height