a pair of angles both between or both outside two line segments that are on opposite sides of the transversal that cuts them.

Corresponding angles are a pair of angles at different vertices on the same side of a transversal in equivalent positions.

Co-interior angles are on the same side of the transversal line and in between the two other lines.

The sum of the interior angles of any triangle

Maths

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

Geometrical properties: polygons

... is 52° because the angles on a line at a point sum to 180°.

... is 45° because the angles in a triangle sum to 180°.

... is 45° because it looks to be half of a right angle.

... is 52° as it is vertically opposite the 52°.

... is 45° because the angles on a line at a point sum to 180°.

Select the statements that can correctly complete the following sentence. The angle marked $$g$$ ...

The {{ }} angles of any triangle sums to 180°.

This diagram _________ that the angles in any triangle sum to 180°.

Which of the following could not be the angles in a triangle?

 ∠ABC as they are equal alternate angles

∠ACB as they are equal alternate angles

as angles on a line at a point sum to 180°

Match each mathematical statement to the correct reasoning in this proof.

The size of the angle marked $$h$$° is {{ }}°.

All three edges and angles are different to each other.

At least two edges and two angles are equal to each other.

All three edges and angles are equal to each other.

Match the type of triangle and the description.

Which angles are always equal to the angle marked $$a$$?

The value of the angle marked $$r$$° is {{ }}°.

The value of the angle marked $$x$$° is {{ }}°.

The value of the angle marked $$m$$° is {{ }}°. 

This lesson will be removed by end of Summer Term 2025.

The sum of the interior angles of any triangle

Lesson outcome

This lesson will be removed by end of Summer Term 2025.