Angle from Chords or Secants: Vertex Inside Circle

Explanations 3

• There are some useful formulas to calculate angles in circles, formed by radii, chords, secants, and tangents. Central Angle ======== A central angle is formed by two intersecti…

  By Sungjae Chung

• Blurb/stub article In the following diagram, we want a simple expression for ∠AXB=∠CXD\angle{AXB} = \angle{CXD}∠AXB=∠CXD. Diagram (secants/chords intersect inside circle)

  By Victor Wang

• When two or more chords cross inside a circle, angles are produced. In the diagram below, chords ACACAC and XYXYXY intersect, creating angles ∠ADX\angle{ADX}∠ADX and ∠CDY\angle{…

  By Vivian Loh