In Euclidean plane geometry, a rectangle is any quadrilateral with four right angles. It can also be defined as an equiangular quadrilateral, since equiangular means that all of its angles are equal (360°/4 = 90°). It can also be defined as a parallelogram containing a right angle. A rectangle with four sides of equal length is a square. The term oblong is occasionally used to refer to a non-square rectangle. A rectangle with vertices ABCD would be denoted as  ABCD.

The word rectangle comes from the Latin rectangulus, which is a combination of rectus (right) and angulus (angle).

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. It is a special case of an antiparallelogram, and 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.

### Insomnia :D

Lunar Eclipse

So happy you woke up! :') :') :') Hope you will be fine soon. Best wishes! (Drawing inspired by...

### Peacock

Lunar Eclipse

After drawing similiar on DMT, Chris suggested to redraw here. Well, here it is ;)

### Mountain Goat

Lunar Eclipse

For Silhouette Saturday.

Lunar Eclipse

### Suits me

Lunar Eclipse

angular suits design concept

"For all our failings, despite our limitations and fallibilities, we humans are capable of greatness."
Carl Sagan
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