Year 8 Mathematics / Properties of Geometrical Figures

Angles in Triangles and Quadrilaterals

Use the angle sum of triangles (180°) and quadrilaterals (360°), the exterior-angle theorem, and the properties of special quadrilaterals to find unknown angles.

Syllabus area

Measurement and Space

Focus

Build Stage 4 geometric fluency — angle relationships, parallel lines, polygon properties and introductory congruence — as the foundation for Year 9 geometric representations and Year 10 geometry proofs.

You can jump straight to the Mastery Quiz whenever you are ready.

Nova Maths

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