related topics
{math, number, function}
{@card@, make, design}
{line, north, south}

In Euclidean plane geometry, a rectangle is any quadrilateral with four right angles. The term "oblong" is occasionally used to refer to a non-square rectangle.[1][2] A rectangle with vertices ABCD would be denoted as Rectanglen.PNG ABCD.

A so-called crossed rectangle is a crossed (self-intersecting) quadrilateral which consists of two opposite sides of a rectangle along with the two diagonals.[3] Its angles are not right angles. Other geometries, such as spherical, elliptic, and hyperbolic, have so-called rectangles with opposite sides equal in length and equal angles that are not right angles.

Rectangles are involved in many tiling problems, such as tiling the plane by rectangles or tiling a rectangle by polygons.



Traditional hierarchy

A rectangle is a special case of a parallelogram, whose opposite sides are equal in length and parallel and connecting sides are perpendicular to each other.

A parallelogram, and hence also a rectangle, is a special case of a trapezium (known as a trapezoid in North America), which has at least one pair of parallel opposite sides.

Full article ▸

related documents
Hilbert's Nullstellensatz
Linearity of integration
Constant folding
Z notation
List of Fourier-related transforms
Euler's theorem
Sigmoid function
Derivative of a constant
Group object
Discrete mathematics
Product of group subsets
Direct sum of groups
Surjective function
Essential singularity
Online algorithm
The Third Manifesto
Greibach normal form
De Bruijn-Newman constant
Hurwitz polynomial
Context-free language
Dense set
Conjugate closure
Recursive language
Lazy initialization
Data element
Location parameter