GeomP5 14.2 ­ Tangents to a Circle
Tangent of a Circle
A line is tangent to a circle iff it touches the circle in exactly one point.
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Line l is tangent to circle P at the point of tangency T. Perpendicular Tangent of a Circle
Perpendicular Tangent Theorem: A radius is perpendicular to a line at a point on the circle iff the line is tangent to the circle at that point.
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Line l is tangent to circle P at the point of tangency T, so what must be true? GeomP5 14.2 ­ Tangents to a Circle
Two Tangent Segments
Exterior Tangent Segments Theorem: If two segments from the same exterior point are tangent to a circle, then those segments are congruent.
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GeomP5 14.2 ­ Tangents to a Circle