18.5 Tangent Lines — The Line That Only Kisses Once
Point 3 of 5
18.5.3 The Tangent-Length Theorem
Core idea
Draw two tangents to a circle from a single outside point and the two tangent segments are equal, while the line from that point to the center also bisects the angle between them.
Module goal. Dig deep into the borderline case of tangency, mastering a tangent's properties, its test, and the tangent-length theorem, then apply them to a triangle's inscribed circle.
eastmath.com · 18.5 Tangent Lines — The Line That Only Kisses Once · 18.5.3 The Tangent-Length Theorem