English contemporary dictionary. 2014.
Japanese theorem for concyclic quadrilaterals — The Japanese theorem states that the centers of the incircles of certain triangles inside a concyclic quadrilateral are vertices of a rectangle.Triangulate an arbitrary concyclic quadrilateral by its diagonals, this yields four overlapping… … Wikipedia
Quadrilateral — This article is about four sided mathematical shapes. For other uses, see Quadrilateral (disambiguation). Quadrilateral Six different types of quadrilaterals Edges and vertices 4 … Wikipedia
Kite (geometry) — Kite A kite showing its equal sides and its inscribed circle. Type Quadrilateral Edges and vertices 4 Symmetry group D1 (*) In Euclid … Wikipedia
Cyclic quadrilateral — Cyclic quadrilaterals. In Euclidean geometry, a cyclic quadrilateral is a quadrilateral whose vertices all lie on a single circle. This circle is called the circumcircle or circumscribed circle, and the vertices are said to be concyclic. Other… … Wikipedia
Tangential quadrilateral — An example of a tangential quadrilateral In Euclidean geometry, a tangential quadrilateral or circumscribed quadrilateral is a convex quadrilateral whose sides all lie tangent to a single circle inscribed within the quadrilateral. This circle is… … Wikipedia
Orthodiagonal quadrilateral — An orthodiagonal quadrilateral. According to the characterization of these quadrilaterals, the two red squares on two opposite sides of the quadrilateral have the same total area as the two blue squares on the other pair of opposite sides. In… … Wikipedia
Rectangle — Family Orthotope Type Quadrilateral Edges and vertices 4 Schläfli symbol {}x{} … Wikipedia
Circumscribed circle — Circumscribed circle, C, and circumcenter, O, of a cyclic polygon, P In geometry, the circumscribed circle or circumcircle of a polygon is a circle which passes through all the vertices of the polygon. The center of this circle is called the… … Wikipedia
Brahmagupta's formula — In geometry, Brahmagupta s formula finds the area of any quadrilateral given the lengths of the sides and some of their angles. In its most common form, it yields the area of quadrilaterals that can be inscribed in a circle. Basic form In its… … Wikipedia
Squaring the circle — Squaring the circle: the areas of this square and this circle are equal. In 1882, it was proven that this figure cannot be constructed in a finite number of steps with an idealized compass and straightedge … Wikipedia
