IGCSE Maths / Working with shape and space

Irregular polygon angle problems 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 an irregular polygon add to the same total as those of any polygon with the same number of sides. Find that total first, then use it to work out missing angles, including angles shown outside the shape or written in terms of x.

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
• Angle sum of a polygon
• Interior and exterior angles of regular polygons
• Finding the number of sides from an angle
• 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