Circle

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Circle

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Circle

Circle (English)

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Definition (keystage 2)

A circle is the set of all points that can be drawn a fixed distance from a single point called the centre.
The set of points forms a path called the circumference of the circle.

Definition (keystage 3)

A circle of radius r and centre point C is the set of all
points which are exactly distance r away from C.
If the radius is r, then the area of a circle is given by:
A = πr²
If the radius is r, then the circumference of a circle is given by:
C = 2πr

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Relations

broader:: (en) Conic section; (en) Ellipse; (en) Figure; (en) Rotundum; (en) Sinusoidal spiral
narrower:: (en) Circle theorem; (en) Circles of a triangle; (en) Circumcircle; (en) Coaxial circles; (en) Epicycle; (en) Escribed circle; (en) Great circle; (en) Incircle or inscribed circle; (en) Lemoine circle; (en) Nine-point circle; (en) Orthogonal circles; (en) Osculating circle; (en) Outscribed circle; (en) Small circle; (en) Unit circle
references:: (en) Euclidean geometry
referenced:: (en) π; (en) Arc of a curve; (en) Area of a circle; (en) Centre of a circle; (en) Chord or secant line; (en) Circular helix; (en) Circular motion; (en) Circumference; (en) Compasses; (en) Concyclic; (en) Construct the centre of a circle; (en) Cosine; (en) Cycle; (en) Cylinder; (en) Descartes' circle theorem; (en) Diameter; (en) Disc; (en) Ecliptic; (en) Intersecting chords theorem; (en) Johnson's theorem; (en) Locus; (en) Miquel's theorem; (en) Pie chart; (en) Power of a point; (en) Radical axis; (en) Radius; (en) Sector; (en) Segment; (en) Semicircle; (en) Sine; (en) Sphere; (en) Spherical cone; (en) Tangent line; (en) Trochoid; (en) Uniform polyhedron

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Circle (English)

Definition (keystage 2)

Definition (keystage 3)

Relations