Circle
Defined by a set of points equidistant from a given point (the centre) that form the circumference.
The diameter is a chord that passes through the centre of the circle.
The radius is any line from the centre to the circumference and so is half the length of the diameter.
| Circle of radius r | |
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| Segment of a circle of radius r | |
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| Sector of a circle of radius r | |
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| Radius of a circle circumscribing a triangle of sides a, b, c | |
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| Radius of a circle inscribed in a triangle of sides a, b, c | |
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See also: Annulus, Arc, Circumference, Concentric Circles, Conic Section, Cylinder, Diameter, Disc, Ellipse, Escribed Circle, Great Circle, Hemisphere, Interior of a Circle, Malfatti Circles, pi, Polygon, Radical Axis, Radical Centre, Radius, Small Circle, Sphere, Tangential.
Subjects: Geometry