Mathematics · Topic revision workspace
Read the notes, score 80% and know 75% of the cards.
Topic overview
Angles & Polygons is a key part of GCSE Mathematics. Build fluency with the method, then apply it to unfamiliar and multi-step problems. Angles on a straight line add up to 180°. Angles around a full point add up to 360°. When two straight lines cross, the opposite angles are equal.
Exam tip
Write every stage of your method. Method marks can still be earned when the final answer is wrong.
Revision notes
Secure these ideas first. Say each definition in your own words, then connect it to the topic overview.
Revision notes
The exam will rarely ask for an isolated definition. Practise selecting the right idea and using it as part of a complete explanation or method.
Core knowledge
Angles on a straight line add up to 180°.
Angles around a full point add up to 360°.
When two straight lines cross, the opposite angles are equal.
Sum of interior angles = (n − 2) × 180° where n is the number of sides.
Exterior angles of any convex polygon always sum to 360°. Each exterior angle of a regular polygon = 360° ÷ n.
A polygon with all sides equal length and all angles equal in size.
The three interior angles of any triangle add up to 180°.
When a transversal crosses parallel lines, alternate angles are equal. They form a Z-shape.
Active recall
Content reviewed 23 July 2026 against the current linked specification.
Mark the notes complete, then test what you can recall.