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Theorem

Inscribed Angle Theorem

Geometry

An inscribed angle is the angle formed at a point on a circle by two chords that meet there, equal to the angle subtended at that point by two other given points on the circle. The inscribed angle theorem relates the measure of such an inscribed angle to the measure of the central angle that intercepts the same arc; its oldest known appearance is in Propositions 20 and 21 of Book 3 of Euclid's Elements. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/

Facts
Classification
Statement Form
Identity or Equation 1
Connections

Has Statement Form

Equation, Concepts

Entity-backed identity for the statement-form enum value this theorem already carries, resolved to a mathematics concept by an explicit value-to-entity map (phase 3 bucket conversion, docs\design_entity_backed_browse_buckets_20260928.md). The statement-form fact itself stays on the theorem unchanged.

Identity, Concepts

Entity-backed identity for the statement-form enum value this theorem already carries, resolved to a mathematics concept by an explicit value-to-entity map (phase 3 bucket conversion, docs\design_entity_backed_browse_buckets_20260928.md). The statement-form fact itself stays on the theorem unchanged.

In Branch

Source Inscribed angle (Wikipedia)
Sources
1. Inscribed angle (Wikipedia)
In Branch: Geometry, Lead sentence
Quote, In Branch: Geometry, Lead sentence
In geometry, an inscribed angle is the angle formed in the interior of a circle when two chords intersect on the circle.
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