75 relations: Angle, Archimedes, Area, Bicone, Bipyramid, Bisection, Bivector, Circumscribed circle, Cone, Congruence (geometry), Convex polygon, Convex polytope, Cross section (geometry), Cube, Determinant, Diagonal, Diamond, Diamonds (suit), Dihedral group, Dual polygon, Euclid, Euclidean geometry, Face (geometry), Flag of Norte de Santander Department, Forum Geometricorum, Golden ratio, Golden rhombus, Great rhombic triacontahedron, Greek language, Icosahedral symmetry, If and only if, Incircle and excircles of a triangle, Inscribed figure, Internal and external angles, Isohedral figure, Isotoxal figure, Kite (geometry), Lattice (group), Law of cosines, List of self-intersecting polygons, Lozenge, Mathematical proof, Merkel-Raute, Orthodiagonal quadrilateral, Parallelogram, Parallelogram law, Perpendicular, Playing card, Polyhedron, Polyiamond, ..., Quadrilateral, Rectangle, Rhombic antenna, Rhombic Chess, Rhombic dodecahedron, Rhombic enneacontahedron, Rhombic hexecontahedron, Rhombic icosahedron, Rhombic triacontahedron, Rhombille tiling, Rhombohedron, Rhomboid, Rhombus of Michaelis, Semiperimeter, Simple polygon, Square, Square tiling, Stellation, Superellipse, Symmetry, Tangential quadrilateral, The Mathematical Gazette, Trapezo-rhombic dodecahedron, Trapezoid, Triangle. Expand index (25 more) » « Shrink index
In plane geometry, an angle is the figure formed by two rays, called the sides of the angle, sharing a common endpoint, called the vertex of the angle.
Archimedes of Syracuse (Ἀρχιμήδης) was a Greek mathematician, physicist, engineer, inventor, and astronomer.
Area is the quantity that expresses the extent of a two-dimensional figure or shape, or planar lamina, in the plane.
A bicone or dicone (bi- comes from Latin, di- from Greek) is the three-dimensional surface of revolution of a rhombus around one of its axes of symmetry.
An n-gonal bipyramid or dipyramid is a polyhedron formed by joining an n-gonal pyramid and its mirror image base-to-base.
In geometry, bisection is the division of something into two equal or congruent parts, usually by a line, which is then called a bisector.
In mathematics, a bivector or 2-vector is a quantity in exterior algebra or geometric algebra that extends the idea of scalars and vectors.
In geometry, the circumscribed circle or circumcircle of a polygon is a circle which passes through all the vertices of the polygon.
A cone is a three-dimensional geometric shape that tapers smoothly from a flat base (frequently, though not necessarily, circular) to a point called the apex or vertex.
In geometry, two figures or objects are congruent if they have the same shape and size, or if one has the same shape and size as the mirror image of the other.
A convex polygon is a simple polygon (not self-intersecting) in which no line segment between two points on the boundary ever goes outside the polygon.
A convex polytope is a special case of a polytope, having the additional property that it is also a convex set of points in the n-dimensional space Rn.
In geometry and science, a cross section is the non-empty intersection of a solid body in three-dimensional space with a plane, or the analog in higher-dimensional spaces.
In geometry, a cube is a three-dimensional solid object bounded by six square faces, facets or sides, with three meeting at each vertex.
In linear algebra, the determinant is a value that can be computed from the elements of a square matrix.
In geometry, a diagonal is a line segment joining two vertices of a polygon or polyhedron, when those vertices are not on the same edge.
Diamond is a solid form of carbon with a diamond cubic crystal structure.
Diamonds or (four-colour deck) is one of the four suits of playing cards in the standard French deck.
In mathematics, a dihedral group is the group of symmetries of a regular polygon, which includes rotations and reflections.
In geometry, polygons are associated into pairs called duals, where the vertices of one correspond to the edges of the other.
Euclid (Εὐκλείδης Eukleidēs; fl. 300 BC), sometimes given the name Euclid of Alexandria to distinguish him from Euclides of Megara, was a Greek mathematician, often referred to as the "founder of geometry" or the "father of geometry".
Euclidean geometry is a mathematical system attributed to Alexandrian Greek mathematician Euclid, which he described in his textbook on geometry: the Elements.
In solid geometry, a face is a flat (planar) surface that forms part of the boundary of a solid object; a three-dimensional solid bounded exclusively by flat faces is a polyhedron.
The Flag of the Department of North Santander was adopted by means of the Ordinance Nº 08, on November 27, 1978 as the official Flag for the Department of Norte de Santander in Colombia.
Forum Geometricorum: A Journal on Classical Euclidean Geometry (often abbreviated Forum Geom.) is a peer-reviewed open-access academic journal that specializes in mathematical research papers on Euclidean geometry.
In mathematics, two quantities are in the golden ratio if their ratio is the same as the ratio of their sum to the larger of the two quantities.
In geometry, a golden rhombus is a rhombus whose diagonals are in the ratio \frac.
In geometry, the great rhombic triacontahedron is a nonconvex isohedral, isotoxal polyhedron.
Greek (Modern Greek: ελληνικά, elliniká, "Greek", ελληνική γλώσσα, ellinikí glóssa, "Greek language") is an independent branch of the Indo-European family of languages, native to Greece and other parts of the Eastern Mediterranean and the Black Sea.
A regular icosahedron has 60 rotational (or orientation-preserving) symmetries, and a symmetry order of 120 including transformations that combine a reflection and a rotation.
In logic and related fields such as mathematics and philosophy, if and only if (shortened iff) is a biconditional logical connective between statements.
In geometry, the incircle or inscribed circle of a triangle is the largest circle contained in the triangle; it touches (is tangent to) the three sides.
An inscribed triangle of a circle In geometry, an inscribed planar shape or solid is one that is enclosed by and "fits snugly" inside another geometric shape or solid.
In geometry, an angle of a polygon is formed by two sides of the polygon that share an endpoint.
In geometry, a polytope of dimension 3 (a polyhedron) or higher is isohedral or face-transitive when all its faces are the same.
In geometry, a polytope (for example, a polygon or a polyhedron), or a tiling, is isotoxal or edge-transitive if its symmetries act transitively on its edges.
In Euclidean geometry, a kite is a quadrilateral whose four sides can be grouped into two pairs of equal-length sides that are adjacent to each other.
In geometry and group theory, a lattice in \mathbbR^n is a subgroup of the additive group \mathbb^n which is isomorphic to the additive group \mathbbZ^n, and which spans the real vector space \mathbb^n.
In trigonometry, the law of cosines (also known as the cosine formula or cosine rule) relates the lengths of the sides of a triangle to the cosine of one of its angles.
Self-intersecting polygons, crossed polygons, or self-crossing polygons are polygons some of whose edges cross each other.
A lozenge (◊), often referred to as a diamond, is a form of rhombus.
In mathematics, a proof is an inferential argument for a mathematical statement.
The Merkel-Raute (German for "Merkel rhombus") is what has been termed Merkel diamond or Triangle of Power by English-speaking media: a hand gesture made by resting one's hands in front of the stomach so that the fingertips meet, with the thumbs and index fingers forming a rough quadrangular shape.
In Euclidean geometry, an orthodiagonal quadrilateral is a quadrilateral in which the diagonals cross at right angles.
In Euclidean geometry, a parallelogram is a simple (non-self-intersecting) quadrilateral with two pairs of parallel sides.
In mathematics, the simplest form of the parallelogram law (also called the parallelogram identity) belongs to elementary geometry.
In elementary geometry, the property of being perpendicular (perpendicularity) is the relationship between two lines which meet at a right angle (90 degrees).
A playing card is a piece of specially prepared heavy paper, thin cardboard, plastic-coated paper, cotton-paper blend, or thin plastic, marked with distinguishing motifs and used as one of a set for playing card games.
In geometry, a polyhedron (plural polyhedra or polyhedrons) is a solid in three dimensions with flat polygonal faces, straight edges and sharp corners or vertices.
A polyiamond (also polyamond or simply iamond) is a polyform whose base form is an equilateral triangle.
In Euclidean plane geometry, a quadrilateral is a polygon with four edges (or sides) and four vertices or corners.
In Euclidean plane geometry, a rectangle is a quadrilateral with four right angles.
A rhombic antenna is a broadband directional wire antenna co-invented by Edmond BruceUS Patent No.
Rhombic Chess is a chess variant for two players created by Tony Paletta in 1980.
In geometry, the rhombic dodecahedron is a convex polyhedron with 12 congruent rhombic faces.
A rhombic enneacontahedron (plural: rhombic enneacontahedra) is a polyhedron composed of 90 rhombic faces; with three, five, or six rhombi meeting at each vertex.
In geometry, a rhombic hexecontahedron is a stellation of the rhombic triacontahedron.
A rhombic icosahedron is a polyhedron shaped like an oblate sphere.
In geometry, the rhombic triacontahedron, sometimes simply called the triacontahedron as it is the most common thirty-faced polyhedron, is a convex polyhedron with 30 rhombic faces.
In geometry, the rhombille tiling, also known as tumbling blocks, reversible cubes, or the dice lattice, is a tessellation of identical 60° rhombi on the Euclidean plane.
In geometry, a rhombohedron is a three-dimensional figure like a cube, except that its faces are not squares but rhombi.
Traditionally, in two-dimensional geometry, a rhomboid is a parallelogram in which adjacent sides are of unequal lengths and angles are non-right angled.
The rhombus of Michaelis, also known as the Michaelis-Raute or the quadrilateral of Michaelis, is a rhombus-shaped contour that is sometimes visible on the lower human back.
In geometry, the semiperimeter of a polygon is half its perimeter.
In geometry a simple polygon is a flat shape consisting of straight, non-intersecting line segments or "sides" that are joined pair-wise to form a closed path.
In geometry, a square is a regular quadrilateral, which means that it has four equal sides and four equal angles (90-degree angles, or (100-gradian angles or right angles). It can also be defined as a rectangle in which two adjacent sides have equal length. A square with vertices ABCD would be denoted.
In geometry, the square tiling, square tessellation or square grid is a regular tiling of the Euclidean plane.
In geometry, stellation is the process of extending a polygon in two dimensions, polyhedron in three dimensions, or, in general, a polytope in n dimensions to form a new figure.
A superellipse, also known as a Lamé curve after Gabriel Lamé, is a closed curve resembling the ellipse, retaining the geometric features of semi-major axis and semi-minor axis, and symmetry about them, but a different overall shape.
Symmetry (from Greek συμμετρία symmetria "agreement in dimensions, due proportion, arrangement") in everyday language refers to a sense of harmonious and beautiful proportion and balance.
In Euclidean geometry, a tangential quadrilateral (sometimes just tangent quadrilateral) or circumscribed quadrilateral is a convex quadrilateral whose sides are all tangent to a single circle within the quadrilateral.
The Mathematical Gazette is an academic journal of mathematics education, published three times yearly, that publishes "articles about the teaching and learning of mathematics with a focus on the 15–20 age range and expositions of attractive areas of mathematics." It was established in 1894 by Edward Mann Langley as the successor to the Reports of the Association for the Improvement of Geometrical Teaching.
In geometry, the trapezo-rhombic dodecahedron or rhombo-trapezoidal dodecahedron is a convex dodecahedron with 6 rhombic and 6 trapezoidal faces.
In Euclidean geometry, a convex quadrilateral with at least one pair of parallel sides is referred to as a trapezoid in American and Canadian English but as a trapezium in English outside North America.
A triangle is a polygon with three edges and three vertices.