- circlesCircle with two intersecting secantsSecant Lines Intersecting a Circle - Arcs and AnglesDemo of Secant Tangent TheoremAngles and Tangents of a CircleCircle and Tangent LinesArc Length in DegreesArc Length, Sector, Segment and Chord calculatorCongruent Chords and their Central AnglesACCESS - Perpendicular DiametersCircle Investigations - angles, arc lengthArc and Angle Inside a Circle10.5 Angles Formed by Chords Intersecting Inside a CircleCongruent ChordsTwo Tangents TheoremAngle Created by Two TangentsCircle PracticeIllustration that two tangents on a circle are congruentCircle Target PracticeArea of a Sector PracticeAngle Properties of Circles