Circles
Class 9 · Mathematics · 6 lessons
This chapter, Circles, is part of the Class 9 Mathematics syllabus under CBSE, Telangana and Andhra Pradesh boards. It contains 6 lessons — starting with Introduction to Circles, Exercise 12.1 — Circle Basics, Exercise 12.2 — Chord and Angle, and more — each with free, step-by-step PDF notes you can study directly in the browser or present in class in fullscreen mode. Work through the lessons in order below; later exercises in this chapter generally build on the concepts introduced in the earlier ones.
Introduction to Circles
Introduction to circle and its parts.
Exercise 12.1 — Circle Basics
Simple problems based on circle and its parts.
Exercise 12.2 — Chord and Angle
Angle subtended by a chord at a point on the circle.
Exercise 12.3 — Perpendiculars from Centre
Perpendiculars from centre to a chord and three points describing a circle.
Exercise 12.4 — Arc and Angle
Angle subtended by an arc of a circle.
Exercise 12.5 — Cyclic Quadrilaterals
Cyclic quadrilaterals and their properties.