Solve problems involving area and perimeter

Maths

In this unit pupils will explain how to calculate the area of a parallelogram and a triangle describing the relationship between scale factors and side lengths. They will describe positions in all four quadrants drawing and translating simple shapes and reflecting them in the axes In the future unit pupils extend their knowledge of plotting coordinates by now plotting non-integer values.

In the prior unit pupils used knowledge of shape properties to draw, sketch and identify shapes. In this unit pupils will explain how to calculate the area of a parallelogram and a triangle. They will describe the relationship between scale factors and side lengths of two shapes. They will describe positions in all 4 quadrants drawing and translating simple shapes and reflecting them in the axes.

Area, perimeter, position and direction

Two shapes with the same area must have the same perimeters. 

Two shapes with the same perimeter must have the same area.

Two shapes with the same area can have different perimeters.

It cannot be increased, shapes with the same area must have the same perimeter.

Rearrange the squares so that more side lengths are on the outside of the shape.

Rearrange the squares so that fewer side lengths are on the outside of the shape

How can the perimeter of this shape be increased without its area changing?

The side length of an equilateral triangle is 8 cm. What is the area of a square with the same perimeter? {{ }} cm². 

The side length of a regular pentagon is 8 cm. What is the area of a square with the same perimeter? {{ }} cm².

How many rectangles can be drawn with whole number side lengths that have an area of 4 cm²?

How many rectangles can be drawn with whole number side lengths that have an area of 16 cm²?

Nothing. They already have the same area 

What can be done so that the shapes have the same area?

It must be a circle, triangle or a square.

What is the area of a square with a side length of 5 cm?

What is the perimeter of a square with a side length of 6 cm?

This lesson will soon be taken down.

Solve problems involving area and perimeter

Lesson outcome