Form 1Form 1MathematicsMathematics

Form 1Form 1MathematicsMathematicsArea of plane shapesArea of plane shapes

Chapter 16Chapter 16

ReviewArea of a rectangle

Area of a rectangle = l x b

E.g. 6 cm

4cm

Area of this rectangle = 6cm x 4cm = 24cm2

ReviewArea of a square

Area of a square = s x s or s2

E.g. 5 cm Area of this square =

5cm x 5cm = 25cm2

ReviewArea of composite shapesWe can find the area of a composite

shape by breaking it up into rectangles and squares.

E.g.This shape can be broken into two rectangles.

10

9

4

3

ReviewArea of composite shapesE.g. Can you find the

dimensions of the rectangles?

10

6

3

4

Now can you find the area of each rectangle?

What is the area of the composite shape?

60 cm2

12cm2

+60 cm2

12cm2 = 72cm2

ReviewArea of composite shapesCan you calculate the

area of this shape?

8

5

35

This shape can be broken into two rectangles.

A Big Oneand

A small one

ReviewArea of composite shapesSo, the area is equal to 8

5 40cm2

subtract

3

5

15cm2 =25c

m2

Area of a parallelogram

To obtain the area of a parallelogram you need two lengths.

The length of the base.

base And the perpendicular height.

Perpendicular height

The area of a parallelogram = base x perpendicular height

Area of ParallelogramE.g.

6cm

4cm

Area of parallelogram =

6cm x 4 cm = 24cm2

Area of triangleArea of a triangle =

½ x base x perpendicular heightWhere …

base

Perpendicular height

Area of triangleE.g. Find the area of

the triangle

5cm

8cm

Area of triangle =

½ x 5 x 8 = 20cm2

Home workReview pg 135 Ex 16c #2, #3Pg 137 Ex 16d #1 to 15Pg 139 Ex 16e #1

Conclusion

Thank you for being your usual

wonderful selves!!!