Circles: Chords, Secants & Tangents
A line intersecting a circle in two places is referred to as a secant. The portion of the secant contained within the circle is called a chord.
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If a line intersects a circle at only a single point, it is called a tangent.
The point at which it intersects with the circle is referred to
as the point of tangency. A tangent is always perpendicular to
the radius of the circle at the point of tangency.
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