Understand that different shapes can have the same perimeter

Maths

Know that a regular polygon has sides that are the same length and angles that are the same size

Know that the perimeter is the distance around a 2D shape

Know that perimeter is measured in units of length and can be found by counting or measuring units

Know that perimeter can be calculated by adding together the side lengths of a 2D shape

Know that the perimeter of a rectangle can be calculated by addition and multiplication

Know that unknown side lengths can be calculated from the perimeter and known side lengths

Understand that the perimeter of a regular polygon can be calculated by multiplication

Calculate the side length of a regular polygon by division where the perimeter is known

Solve problems involving the perimeter and side lengths of polygons

In this unit pupil will learn perimeter as the distance around the edge of a 2D shape. They will learn perimeter is measured in units of length found by counting units and by calculating by adding the side lengths of a 2D shape. In the future unit pupils will pupils will complete and compose symmetrical shapes from two congruent shapes and investigate lines of symmetry in 2D shapes. 

In the prior unit pupils investigated ways to compose and decompose polygons. They investigated quadrilaterals with and without parallel and perpendicular sides. In this unit pupil will learn perimeter as the distance around the edge of a 2D shape. They will learn perimeter is measured in units of length found by counting units and by calculating by adding the side lengths of a 2D shape.

In this unit pupil will learn perimeter as the distance around the edge of a 2D shape. They will learn perimeter is measured in units of length found by counting units and by calculating by adding the side lengths of a 2D shape.

Perimeter

Two different shapes can have the same perimeter. 

Two different shapes cannot have the same perimeter. 

Two different shapes may or may not have the same perimeter. 

Always, sometimes or never true? A regular polygon can have the same perimeter as a shape with curved sides. 

Select the two shapes with the same perimeter.

The shapes are different but the perimeter is the same.

The shapes are different and the perimeter is different.

It is impossible to tell whether the perimeter is the same or different.

Which statement is true of the polygons created inside these number rods?

The rectangles could have the same perimeter.

The rectangles cannot have equal perimeter because sides lengths are different.

B has the longest perimeter because it has the longest side length.

Which of these statements is true about these three rectangles?

Match the number of sides to the shape name.

Select all of the names of shapes that are polygons.

Which of these shapes are regular polygons?

Rearrange these phrases to make a sentence.

Which of these shows the perimeter of the triangle?

In terms of perimeter, which of the statements are true of this image?

Understand that different shapes can have the same perimeter

Lesson outcome