Curated OER
Chords of a Circle
Teach how to differentiate between chords and perpendicular bisectors. In this geometry lesson, students relate the properties of chords and circle to solving right triangle. They define what makes two chords congruent in side a circle.
Wolfram Research
Wolfram Math World: Chord
Describes what a chord is and shows a diagram and shows how to find areas using integral calculus.