1. Circle
Definition: a set of all points in a plane at a given distance from a given point (center/origin).
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2. Radius
Definition: The given distance from center/origin of the circle to the edge.
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3. Diameter
Definition: A chord that passes through the origin/center. Picture:

4. Chord
Definition: A line segment whose endpoints lie on the circle. The diameter is the longest chord.
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5. Tangent
Definition: A line that touches (intersects) the circle only once. The point the circle touches the circle is named the point of tangency.
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6. Semicircle
Definition: Half of a circle.
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7. Identify Each Part of the Circle…
Chord
Radius
Diameter
Tangent