GCSE Maths: Properties of 2D Shapes
Calculate interior and exterior angles of regular and irregular polygons. Practise it with adaptive questions for AQA, Edexcel, OCR and Eduqas.
What you need to know
The concepts examiners test on properties of 2d shapes, and what each one is really asking.
Where marks get lost
The exam technique that separates a correct method from a correct answer.
- Confusing interior and exterior angles
- Forgetting the -2 in the interior sum formula: (n-2)×180
- Assuming irregular polygons have equal angles
- Thinking the sum of exterior angles changes with the number of sides (it's ALWAYS 360)
Properties of 2D Shapes questions students ask
Is Properties of 2D Shapes on the Foundation paper?
Yes. Properties of 2D Shapes appears at both Foundation and Higher tier, though Higher papers take it further.
What should I know before starting Properties of 2D Shapes?
It builds on Angle facts on a straight line and Solving linear equations. If those feel shaky, practise them first — Properties of 2D Shapes questions assume them.
What is the most common mistake in Properties of 2D Shapes?
Confusing interior and exterior angles.
Which exam boards cover Properties of 2D Shapes?
All four we support — AQA, Edexcel, OCR and Eduqas. GCSE Maths subject content is set by the DfE, so the topic is common to every board; what changes is the paper structure and the grade boundaries.