Squareness of Parallelograms
- Judah L Schwartz
A rhombus is a parallelogram with perpendicular diagonals that in certain circumstances is a square. A rectangle is a parallelogram with interior right angles that in certain circumstances is a square. Can you devise a measure of squareness of parallelograms that allows you to tell how much "squarer" one parallelogram is than another? Can you devise a second and different measure of squareness of parallelograms? Under what circumstances might one such measure be preferable to the other?