IGCSE Maths / Working with shape and space

Angle sum of a polygon revision notes

Edexcel International GCSE Maths (4MA1), chapter 11: Working with shape and space, specification point 4.2e. Part of the full course.

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The interior angles of a polygon can be found by splitting it into triangles. This gives a formula for the total angle sum and helps you calculate a missing angle with a clear reason.

More lessons in Working with shape and space

• Angles at a point and on a line
• Angles in parallel lines
• Angle sum of a triangle
• Exterior angle of a triangle
• Angles in special triangles
• Angle sum of a quadrilateral
• Properties of quadrilaterals
• Writing geometrical reasons
• Interior and exterior angles of regular polygons
• Finding the number of sides from an angle
• Irregular polygon angle problems
• Perimeter and area of rectangles and triangles
• Area of a parallelogram
• Area of a trapezium
• Names of solids: faces, edges and vertices
• Surface area of a cuboid
• Surface area of a triangular prism
• Volume of a prism
• Compound prisms and volume units
• Time intervals, money and currency
• Converting units of length, area and volume