A

David

Darling

rectangle

A rectangle is a quadrilateral whose interior angles are all 90°. If all of its sides are the same length, it is a square. A rectangle is a special case of a parallelogram.

 

An oblong is alternate name for any rectangle that is not a square. The word comes from the Latin ob ("excessive") and longus ("long"). See also oblong number.

 

The smallest square that can be cut into m × n rectangles, such that all m and n are different integers, is the 11 × 11 square, and the tiling uses five rectangles. The smallest rectangle that can be cut into m × n rectangles, such that all m and n are different integers, is the 9 × 13 rectangle, and this tiling also uses five rectangles.