Chords, Tangents & Inscribed Angles
Section: GeometryBank code: GEO-CTSGRE frequency: MediumPro
1. Core Idea
This capsule covers the circle's lines: chords, tangents and the angles they create.
Two structural facts do most of the work:
- A radius drawn to the point of tangency is perpendicular to the tangent.
- A radius perpendicular to a chord bisects that chord.
Both create right triangles — which is why almost every question here ends in Pythagoras.
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