Geometry#
Sections#
Figures#
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0287-0212 BCEArchimedes of Syracuse[ w ]
250 BCEMeasurement of a Circle Κύκλου μέτρησις
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1783-1864Brianchon, Charles Julien[ w ]
1845-1922Brocard, Henri[ w ]
1647-1734Ceva, Giovanni[ w ]
1842-1906De Longchamps, Gaston Albert Gohierre[ w ]
0300 BCEEuclid[ w ] Elements
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0408-0355 BCEEudoxus of Cnidus[ w ]
1884-1954Gossard, Harry Clinton[ w ]
1861-1940Heath, T. L.[ w ]
1846-1934Kiepert, Ludvig[ w ]
1942-----Kimberling, Clark[ w ]
1840-1912Lemoine, Émile[ w ]
1860-1937Morley, Frank[ w ]
0290-0350Pappus of Alexandria[ w ]
1748-1819Playfair, John[ w ]
0570-0495 BCEPythagoras of Samos[ w ]
1831-1907Routh, Edward[ w ]
1896-1986Schiffler, Kurt[ w ]
1796-1863Steiner, Jakob[ w ]
1803-1882Von Nagel, Christian Heinrich
Terms#
[ w ] Biangular Coordinates
[ w ] Bipolar Coordinates
[ w ] Bipolar Coordinates, Two-Center
[ w ] Elliptic Coordinates
[ w ] Polar Coordinates
[ w ] Spherical Coordinates
[ w ] Two-Center Bipolar Coordinates
[ w ] 3D Projection
[ w ] Acute Triangle
[ w ] Altitude
[ w ] Angle
[ w ] Angle, Central
[ w ] Angle, External
[ w ] Angle, Hyperbolic
[ w ] Angle, Inscribed
[ w ] Angle, Internal
[ w ] Angle, Right
[ w ] Angle, Subtended
[ w ] Angle Bisector Theorem
[ w ] Angle Trisection
[ w ] Anharmonic Ratio (Cross-Ratio, Double Ratio)
[ w ] Antiparallelogram
[ w ] Antiprism
[ w ] Antiprism, Pentagonal
[ w ] Apeirogon
[ w ] Apeirogon, Skew
[ w ] Apex
[ w ] Apoapsis
[ w ] Apollonian Circle
[ w ] Apollonius’ Problem
[ w ] Apothem
[ w ] Apsis
[ w ] Arc, Circular
[ w ] Arc Length
[ w ] Archimedean Solid
[ w ] Area
[ w ] Axial Symmetry
[ w ] Axiality
[ w ] Axis of Perspectivity
[ w ] Ball
[ w ] Base
[ w ] Bipyramid (Dipyramid, Double Pyramid)
[ w ] Bipyramid, Pentagonal
[ w ] Bisection
[ w ] Brianchon’s Theorem
[ w ] Brocard Circle
[ w ] Brocard Point
[ w ] Brocard Triangle
[ w ] Catalan Solid
[ w ] Cathetus
[ w ] Center
[ w ] Center, Homothetic
[ w ] Center, Morley
[ w ] Center, Nine-Point
[ w ] Center, Power
[ w ] Center, Spieker
[ w ] Center, Triangle
[ w ] Center of Perspectivity
[ w ] Center of Similitude (Homothetic Center)
[ w ] Central Angle
[ w ] Central Line
[ w ] Centroid
[ w ] Ceva’s Theorem
[ w ] Cevian
[ w ] Chiral Polytope
[ w ] Chirality
[ w ] Chord
[ w ] Circle
[ w ] Circle, Apollonian
[ w ] Circle, Brocard
[ w ] Circle, Circumscribed
[ w ] Circle, Escribed
[ w ] Circle, Inscribed
[ w ] Circle, Nine-Point
[ w ] Circle, Spieker
[ w ] Circular Arc
[ w ] Circular Segment
[ w ] Circular Triangle
[ w ] Circumcenter
[ w ] Circumconic
[ w ] Circumference
[ w ] Circumradius
[ w ] Circumscribed Circle
[ w ] Circumscribed Polygon (Tangential Polygon)
[ w ] Circumscribed Sphere
[ w ] Cleaver
[ w ] Collinearity
[ w ] Compass
[ w ] Compass Equivalence Theorem
[ w ] Complex Line
[ w ] Complex Plane
[ w ] Cone
[ w ] Concentricity
[ w ] Concurrent Line
[ w ] Concyclic Point
[ w ] Congruence
[ w ] Conic, Kiepert
[ w ] Conic, Steiner
[ w ] Constructible Polygon
[ w ] Convex Hull
[ w ] Convex Polygon
[ w ] Conway Polyhedron Notation
[ w ] Coordinate Space, Real
[ w ] Coordinates, Trilinear
[ w ] Coplanarity
[ w ] Cross-Ratio (Anharmonic Ratio, Double Ratio)
[ w ] Cube
[ w ] Cubic Honeycomb
[ w ] Cuboid
[ w ] Cuboid, Rectangular
[ w ] Curve
[ w ] Curve, Intersection
[ w ] Curve, Inverse
[ w ] Curve, Parallel
[ w ] Curvilinear Perspective
[ w ] Cylinder
[ w ] Cylinder, Right Circular
[ w ] De Longchamps Point
[ w ] Deltahedron
[ w ] Diagonal
[ w ] Diameter
[ w ] Dihedron
[ w ] Dipyramid (Bipyramid, Double Pyramid)
[ w ] Directrix
[ w ] Discrete Geometry
[ w ] Disk
[ w ] Disk Segment
[ w ] distance from a point to a line
[ w ] Dodecahedron, Rhombic
[ w ] Double Pyramid (Bipyramid, Dipyramid)
[ w ] Double Ratio (Anharmonic Ratio, Cross-Ratio)
[ w ] doubling the cube
[ w ] Dual Polyhedron
[ w ] Edge
[ w ] Edge-Transitivity (Isotoxality)
[ w ] Ellipse
[ w ] Ellipse, Steiner
[ w ] Elongated Square Gyrobicopula
[ w ] Equiangular Polygon
[ w ] Equidistance
[ w ] Equilateral Polygon
[ w ] Equilateral Triangle
[ w ] Escribed Circle (Excircle)
[ w ] Euclidean Geometry
[ w ] Euler Line
[ [w](https://en.wikipedia.org/wiki/Euler% 27s_theorem_in_geometry)] Euler’s Theorem, in geometry
[ w ] Excircle (Escribed Circle)
[ w ] Exeter Point
[ w ] External Angle
[ w ] Extouch Triangle
[ w ] Face
[ w ] Faceting
[ w ] Frustum
[ w ] Galois Geometry
[ w ] Generatrix
[ w ] Geodesic
[ w ] Geometry
[ w ] Geometry, Computational
[ w ] Geometry, Descriptive
[ w ] Geometry, Differential
[ w ] Geometry, Diophantine
[ w ] Geometry, Discrete
[ w ] Geometry, Euclidean
[ w ] Geometry, Galois
[ w ] Geometry, history
[ w ] Geometry, Hyperbolic
[ w ] Geometry, Incidence
[ w ] Geometry, Inversive
[ w ] Geometry, Modern Triangle
[ w ] Geometry, Non Euclidean
[ w ] Geometry, Projective
[ w ] Geometry, Riemannian
[ w ] Geometry, Solid
[ w ] Geometry, Spherical
[ w ] Geometry, Symplectic
[ w ] Geometry, Synthetic
[ w ] Glissette
[ w ] Gossard Perspector
[ w ] Grebe Point (Lemoine Point, Symmedian Point)
[ w ] Half-Space
[ w ] Homothetic Center (Center of Similitude)
[ w ] Hosohedron
[ w ] Hyperbola
[ w ] Hyperbolic Angle
[ w ] Hyperbolic Motion
[ w ] Hyperplane
[ w ] Hyperplane, Supporting
[ w ] Hypersphere (\(n\)-Sphere)
[ w ] Hypersurface
[ w ] Hypotenuse
[ w ] Icosahedron
[ w ] Incenter
[ w ] Incidence Geometry
[ w ] Incircle (Inscribed Circle)
[ w ] Inconic
[ w ] Inellipse
[ w ] Inellipse, Mandart
[ w ] Inellipse, Steiner
[ w ] Internal Angle
[ w ] Inscribed Angle
[ w ] Inscribed Circle (Incircle)
[ w ] Intersection
[ w ] Intersection Curve
[ w ] Inverse Curve
[ w ] Inversive Geometry
[ w ] Isogonality (Vertex-Transitivity)
[ w ] Isotoxality (Edge-Transitivity)
[ w ] Isosceles Triangle
[ w ] Johnson Solid
[ w ] Kiepert Conic
[ w ] Lemoine Point (Grebe Point, Symmedian Point)
[ w ] Lemoine’s Problem
[ w ] Lens
[ w ] Line
[ w ] Line, Central
[ w ] Line, Complex
[ w ] Line, Concurrent
[ w ] Line, Euler
[ w ] Line, Simson
[ w ] Line, Skew
[ w ] Line, Supporting
[ w ] Line Element
[ w ] Line of Apsides
[ w ] Line Segment
[ w ] Locus
[ w ] Lune of Hippocrates
[ w ] Mandart Inellipse
[ w ] Medial Triangle (Midpoint Triangle)
[ w ] Median
[ w ] Midpoint
[ w ] Midpoint Triangle (Medial Triangle)
[ w ] Mittenpunkt
[ w ] Modern Triangle Geometry
[ w ] Morley Center
[ w ] Moreley’s Trisector Theorem
[ w ] Myriagon
[ w ] \(n\)-Sphere (Hypersphere)
[ w ] Nagel Point
[ w ] Neusis
[ w ] Nine-Point Center
[ w ] Nine-Point Circle
[ w ] Non Euclidean Geometry
[ w ] Normal
[ w ] Obtuse Triangle
[ w ] Orthocenter
[ w ] Orthocentric System
[ w ] Orthogonality
[ w ] Oval
[ w ] Pappus’ Hexagon Theorem
[ w ] Parabola
[ w ] Parallel Curve
[ w ] Parallel Line, distance
[ w ] Parallel Postulate
[ w ] Parallelepiped
[ w ] Parallelism
[ w ] Parallelogon
[ w ] Parallelogram
[ w ] Parallelohedron
[ w ] Pencil
[ w ] Pentagonal Antiprism
[ w ] Pentagonal Bipyramid
[ w ] Periapsis
[ w ] Perimeter
[ w ] Perspective
[ w ] Perspective, Curvilinear
[ w ] Perspectivity
[ w ] Petersen-Morley Theorem
[ w ] Plane
[ w ] Plane, Complex
[ w ] Playfair’s Axiom
[ w ] Point
[ w ] Point, Brocard
[ w ] Point, Concyclic
[ w ] Point, De Longchamps
[ w ] Point, Exeter
[ w ] Point, Grebe (Lemoine, Symmedian)
[ w ] Point, Lemoine (Grebe, Symmedian)
[ w ] Point, Nagel
[ w ] Point, Schiffler
[ w ] Point, Steiner
[ w ] Point, Symmedian (Grebe, Lemoine)
[ w ] Point, Trisected Perimeter
[ w ] Point Reflection
[ w ] Polarity, Trilinear
[ w ] Polygon
[ w ] Polygon, Circumscribed (Tangential)
[ w ] Polygon, Constructible
[ w ] Polygon, Convex
[ w ] Polygon, Equiangular
[ w ] Polygon, Equilateral
[ w ] Polygon, Regular
[ w ] Polygon, Simple
[ w ] Polygon, Skew
[ w ] Polygon, Star
[ w ] Polygon, Tangential (Circumscribed)
[ w ] Polygonal Chain
[ w ] Polyhedron
[ w ] Polyhedron, Dual
[ w ] Polyhedron, Quasiregular
[ w ] Polyhedron, Semiregular
[ w ] Polyhedron, Snub
[ w ] Polyhedron, Spherical
[ w ] Polytope
[ w ] Polytope, Chiral
[ w ] Polytope, Regular
[ w ] Pons Asinorum
[ w ] Power Center
[ w ] Prism
[ w ] Prismatoid
[ w ] Product, Triple
[ w ] Projection, 3D
[ w ] Pyramid
[ w ] Pyramid, Double (Bipyramid, Dipyramid)
[ w ] Pythagorean Theorem
[ w ] Quadrilateral
[ w ] Quasiregular Polyhedron
[ w ] Radial Symmetry (Rotational Symmetry)
[ w ] Radian
[ w ] Radius
[ w ] Ratio, Anharmonic (Cross, Double)
[ w ] Ratio, Cross (Anharmonic, Double)
[ w ] Ratio, Double (Anharmonic, Cross)
[ w ] Real Coordinate Space
[ w ] Rectangle
[ w ] Rectangular, Cuboid
[ w ] Reflection
[ w ] Reflection Symmetry
[ w ] Reflection, Point
[ w ] Regular Polygon
[ w ] Regular Polytope
[ w ] Rhombic Dodecahedron
[ w ] Rhombohedron
[ w ] Riemann Sphere
[ w ] Right Angle
[ w ] Right Circular Cylinder
[ w ] Right Triangle
[ w ] Right Triangle, Special
[ w ] Rotational Symmetry (Radial Symmetry)
[ w ] Routh’s Theorem
[ w ] Ruler-and-Compass Construction
[ w ] Sagitta
[ w ] Scalene Triangle
[ w ] Scaling
[ w ] Schiffler Point
[ w ] Secant
[ w ] Segment, Circular (Disk)
[ w ] Segment, Disk (Circular)
[ w ] Segment, Line
[ w ] Segment, Spherical
[ w ] Semicircle
[ w ] Semiperimeter
[ w ] Semiregular Polyhedron
[ w ] Similarity
[ w ] Simple Polygon
[ w ] Simson Line
[ w ] Skew Apeirogon
[ w ] Skew Line
[ w ] Skew Polygon
[ w ] Snub Polyhedron
[ w ] Solid, Archimedean
[ w ] Solid, Catalan
[ w ] Solid, Johnson
[ w ] Solid Geometry
[ w ] Space, Real Coordinate
[ w ] Special Right Triangle
[ w ] Sphere
[ w ] Sphere, Circumscribed
[ w ] Sphere, Riemann
[ w ] Spherical Cap
[ w ] Spherical Polyhedron
[ w ] Spherical Segment
[ w ] Spieker Center
[ w ] Spieker Circle
[ w ] Spiral
[ w ] Spirolateral
[ w ] Splitter
[ w ] squaring the circle
[ w ] Star Polygon
[ w ] Steiner Conic
[ w ] Steiner Ellipse
[ w ] Steiner Inellipse
[ w ] Steiner Point
[ w ] Stellation
[ w ] Straightedge
[ w ] Subtended Angle
[ w ] Supporting Hyperplane
[ w ] Supporting Line
[ w ] Surface
[ w ] Symmedian
[ w ] Symmedian Point (Grebe Point, Lemoine Point)
[ w ] Symmetry, Axial
[ w ] Symmetry, Radial (Rotational)
[ w ] Symmetry, Reflection
[ w ] Symmetry, Rotational (Radial)
[ w ] Symmetry, Translational
[ w ] Tangent
[ w ] Tangential Polygon (Circumscribed Polygon)
[ w ] Tangential Triangle
[ w ] Tessellation
[ w ] Tetrakis Hexahedron
[ w ] Thales’ Theorem
[ w ] Tomahawk
[ w ] Translational Symmetry
[ w ] Trapezohedron
[ w ] Trapezohedron, Trigonal
[ w ] Trapezoid
[ w ] Triangle
[ w ] Triangle, Acute
[ w ] Triangle, Brocard
[ w ] Triangle, Circular
[ w ] Triangle, Equilateral
[ w ] Triangle, Extouch
[ w ] Triangle, Isosceles
[ w ] Triangle, Medial (Midpoint)
[ w ] Triangle, Midpoint (Medial)
[ w ] Triangle, Obtuse
[ w ] Triangle, Right
[ w ] Triangle, Scalene
[ w ] Triangle, Special Right
[ w ] Triangle, Tangential
[ w ] Triangle Center
[ w ] Triangle Inequalities
[ w ] Trigonal Trapezohedron
[ w ] Trilinear Coordinates
[ w ] Trilinear Polarity
[ w ] Triple Product
[ w ] Trisected Perimeter Point
[ w ] Trisection, Angle
[ w ] Unital
[ w ] Upper Bound Theorem
[ w ] Vesica Piscis
[ w ] Vertex
[ w ] Vertex-Transitivity (Isogonality)
[ w ] Viviani’s Theorem
[ w ] Volume
[ w ] Zonogon
[ w ] Zonohedron
[W] Polygon
[W] Trigon (Triangle)
[W] Tetragon (Quadrilateral)
[W] Pentagon
[W] Hexagon
[W] Heptagon
[W] Octagon
[W] Nonagon
[W] Decagon
[W] Hendecagon
[W] Dodecagon
[W] Apeirogon
[W] Equilateral Polygon
[W] Star Polygon
[W] Pentagram
[W] Hexagram
[W] Heptagram
[W] Octagram
[W] Nonagram
[W] Decagram
[W] Hendecagram
[W] Dodecagram
[W] Solid Geometry
[W] Quadric Surface
[W] Ellipsoid
[W] Paraboloid
[W] Hyperboloid
One-Sheet Hyperboloid (Hyperbolic Hyperboloid)
Two-Sheet Hyperboloid (Elliptic Hyperboloid)
[W] Superquadrics
[W] Platonic Solid
[W] Cube (Square Cuboid)
[W] Octahedron
[W] Regular Dodecahedron
[W] Regular Icosahedron
[W] Tetrahedron (Triangular Pyramid)
[W] Archimedean Solid
[W] Cuboctahedron
[W] Icosidodecahedron
[W] Rhombicosidodecahedron
[W] Rhombicuboctahedron
[W] Snub Cube
[W] Snub Dodecahedron
[W] Truncated Cube
[W] Truncated Cuboctahedron
[W] Truncated Dodecahedron
[W] Truncated Icosahedron
[W] Truncated Icosidodecahedron
[W] Truncated Octahedron
[W] Truncated Tetrahedron
[W] Catalan Solid
[W] Rhombic Triacontahedron
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