noun
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geometrya shape where every point along its perimeter is an equal distance from its center."the circle with a radius of one is called the unit circle."
A circle is a shape where every point along its perimeter is an equal distance from its center.
Since a circle is used throughout math, many of its properties and attributes are given specific names.
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Radius The radius is the distance from the center of the circle to any point along the perimeter of the circle. |
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Circumference The circumference is the length around the perimeter of the circle. |
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Diameter The diameter is the distance between any two points along the perimeter of the circle that passes through the center of the circle. |
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Area The area of a circle is the amount of two-dimensional space that fits inside the perimeter of the circle. |
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Circle Constant The circle constant (tau) is a naturally occuring number calculated by dividing the circumference of any circle by its radius. |
A sphere is a three-dimensional geometric shape that is perfectly symmetrical around its center. All points on the surface of a sphere are equidistant from its center.