A circle is a line forming a closed loop, every point on which is a fixed distance from a center point.

Properties of circles are the following:

1. Center

2. Radius

3. Diameter

4. Circumference

5. Area

6. Chord

7. Tangent

8. Secant..

**and also Wikipedia defines circle as a simple shape of Euclidean geometry consisting of those points in a plane which are equidistant from a given point, the centre (also spelled "center").

A circle is an ellipse where the minor and major radii are equal in length. It is given by the equation (x-h)^2/r^2+(y-k)^2/r^2=1. In this equation the center of the circle is located at point h,k and r^2 represent the length of either radius squared. Finally the circumference of a circle that is its perimeter is 2*Pi*r and its area is Pi*r^2.

...The set of points in a plane which are at a constant distance 'r'(>=0)from a fixed point c is called a circle..The fixed point is called "center" and the constant distance "r" is called "the radius of the circle"..........

The equation of the circle is

A circle is the path traced by a point that maintains a fixed distance from a point called the centre of the circle and the fixed distance is called the radius of the circle.

...The figure formed by the group of points that are an equal distance from a point, or center. The angles of a circle add up to 360 degrees.

...Your questions are the best.

A circle is a simple Euclidean geometric shape. For an example, see the letter O.

A circle is an infinite amount of points, which are all at a constant distance(radius) from a fix point (center).

...A closed plane curve consisting of all points at a given distance from a point within it called the center.

...A circle has no end and no beginning. Most circles are measured by Radius, circumference or diameter.

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