an angle formed inside a polygon by two of its edges.

an angle on the outside of a polygon between an extension of an edge and its adjacent edge.

Exterior angles of polygons

Maths

Checking understanding of angles from KS2

Securing understanding of angles from KS2

Formalising understanding of triangles from KS2

Formal angle notation

Corresponding angles

Alternate angles

Co-interior angles

Angles on parallel lines traversed by a straight line

The sum of the interior angles of any triangle

Using the sum of the interior angles of a triangle

Interior angles of a polygon

Deriving the sum of interior angles in multiple ways

Interior and exterior angles of regular polygons

Missing angles

Problem solving with polygons

This unit gives pupils the opportunity to explore polygons and begin to generalise their understanding of interior/exterior angles in regular polygons. In the future unit, pupils will use the geometrical properties of a rhombus to perform various constructions

In this unit, pupils learnt how to calculate with angles at a point and angles on a straight line. In this unit, pupils extend their knowledge about angles in lines

In this unit pupils will investigate internal and external angles of polygons and angles made with a transveral and parallel lines. Pupils will develop their ability to formally prove properties of polygons to generalise.

Geometrical properties: polygons

An interior angle and its adjacent exterior angle sum to {{}}°.

In which diagram is an exterior angle marked?

Exterior angles in a polygon sum to {{}}°.

An {{}} angle is an angle on the outside of a polygon between an extension of an edge and its adjacent edge.

Adjacent angles on a straight line sum to {{}}°.

A heptagon is a 7-sided polygon. The sum of its interior angles is {{}}°.

Solve the equation: $$5x + 40 = 360$$. $$x = $${{}}

Exterior angles of polygons

Lesson outcome