Area

The amount of surface covered by each shape is called its area. Which one of these carpets takes up more floor space? They have the same area.

The usual way of measuring area is to find the number of squares a shape covers 1 cm 1cm 1 cm 1cm Here we have a square measuring 1 cm by 1 cm We say the square has an area of 1

Here we have a square measuring 2 cm by 2 cm If we place it on some centimetre squared paper we can see it covers 4 squares We say the square has an area of 4

Placing each one onto centimetre paper we have: What is the area of the following rectangles? A B C A B C The area of rectangle C is 12 The area of rectangle B is 24 The area of rectangle A is 6

The area of a rectangle A B C Length = 2 cm Width = 6 cm The area of rectangle C is Length = 3 cm Width = 2 cm The area of rectangle A is Length = 6 cm Width = 4 cm The area of rectangle B is

The area of a rectangle Length (l) Width (w)

Area of a triangle Cut out the shaded area and place onto the left part of the triangle. Cut out the shaded area and place onto the right part of the triangle. Draw a rectangle around it Draw a triangle onto squared paper height height base Notice the area of the rectangle is What do you notice?

base height Area of a triangle We notice the area of the triangle is

base height Area of a triangle

Area of a parallelogram A parallelogram is a quadrilateral, which its opposite sides are parallel but are of unequal length base height base height What do you notice? Consider the shaded part and cut it off and place it on the other side. The area of the parallelogram is base height.

Area of a parallelogram base (b) height (h) Area of a parallelogram The area of a parallelogram is

Area of a trapezium Split the trapezium into two triangles h a b

Split the trapezium into two triangles b a A B Area of triangle A Area of triangle B Area of trapezium

Area of a trapezium To find the area of a trapezium you must add together the two parallel sides, multiply by the height and divide by 2. h a b

The area of a kite Place the triangle on the other side. Place this triangle on the other side. Cut out the shaded triangle. Cut out shaded triangle. Draw on diagonal length b. Draw a kite onto squared paper Draw on diagonal length a b a

The area of a kite Your diagram should look like this. b The area of a kite What do you notice? We now have a rectangle The length (l) is b The width (w) is b The area

The area of a kite Area of a kite is half the product of its diagonals b a The area of a kite Area of a kite is half the product of its diagonals

Area of Shapes Rectangle Triangle Parallelogram Trapezium Kite length (l) width (w) base (b) height (h) base (b) height (h) Trapezium Kite b b a h a