3.37 Circle Theorems with Intersecting Chords IGCSE Higher PowerPoint Lesson

In this 42-slide lesson, pupils will be introduced to key theorems that describe relationships between angles, chords, tangents, and radii within and around a circle. Through guided discovery and visual reasoning, students will explore and apply theorems such as:

• The angle at the centre is twice the angle at the circumference

• Angles in the same segment are equal

• The angle in a semicircle is 90°

• Opposite angles in a cyclic quadrilateral sum to 180°

• The tangent to a circle is perpendicular to the radius

• Tangents from an external point are equal in length

• Alternate segment theorem

• Intersecting chords theorems

Note this lesson is for the higher tier. This lesson is for IGCSE exam boards that require knowledge of the intersecting chord theorems.

The lesson includes:

• Clear, guided examples

• Discussion opportunities from Think, Pair, Share

• Mini whiteboard section to check understanding and clarify misconceptions

• Four structured tasks to practise key skills

• Challenge activity to extend and deepen learning

Perfect for engaging learners while reinforcing essential geometry concepts.