Final answer:
A circle is the set of all points in a plane that are equidistant from a given point called the center.
Step-by-step explanation:
A circle is defined as the set of all points in a plane that are the same distance from a given point called the center. This means that any point on the circumference of the circle is equidistant from the center. The radius of a circle is the distance from the center to any point on the circumference.
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