2. Area 1 Contents 1.GeneralGeneral 2.ShapesShapes 3.Quadrilaterals and TrianglesQuadrilaterals and Triangles 4.Circles and SectorsCircles and Sectors 5.Composite AreasComposite Areas Press “ctrl-A”

3. Area 2 Conversions mm 2 cm 2 m2m2m2m2ha km 2 x 100 x 10 000 ÷ 100 ÷ 10 000

4. Area 3 Introduction is the space inside a shape. We can find the area by counting squares. 123 4 56 7 891011121314151617 1819 20 21 22 23 24 25 26 27 2829 3031323334353637 38 39 40 41 42 43 44 45 45.5 46 46.5 47

5. Area 4 4.3 Formula (1/7) Counting squares is not easy. We have formulas for the shapes. Square Rectangle ParallelogramRhombus TrapeziumTriangleCircle

6. Area 5 4.3 Area of Squares (2/7) A = s 2 6.3 m = 6.3 2 = 39.69 m 2

7. Area 6 4.3 Area of Rectangles (3/7) A = L x B 3.3 m = 6.4 x 3.3 = 21.12 m 2 6.4 m

8. Area 7 4.3 Area of Parallelogram (4/7) A = B x H 5.3 m = 5.3 x 6.4 = 33.92 m 2 6.4 m Slanting Parallelogram

9. Area 8 4.3 Area of Trapezium (6/7) A = 0.5 x (a +b) x h 4 m = 0.5 x (3 + 7) x 4 = 20 m 2 7 m 3 m 4 m

10. Area 9 4.3 Area of Circle (1/5)r A = π x r 2 3m 3 = π x 3 2 = 28.274 333… ≈ 28.3 m 2

11. Area 10 4.4 Area of Sector (2/5) 55 o 3cm A = x π r 2 θ 360 = x π x 3 2 55 360 = 4.319 689 899 = 4.3 cm 2 Find Area

12. Area 11 4.4 Area of Sector (3/5)7cm A = x π r 2 θ 360 = x π x 7 2 135 360 = 57.726 765 01 = 57.7 cm 2 135 o Find Area

13. Area 12 4.4 Area of Sector (4/5) 45 o r A = x π r 2 θ 360 48 = x π x r 2 45 360 A=48cm 2 Find Radius r 2 = x 48 360 45 π ÷45x360 ÷ π r = 11.055 812 783 = 11.06 cm Hint (360÷(45x π )x48)

14. Area 13 4.4 Area of Sector (5/5) A = x π r 2 θ 360 96 = x π x r 2 120 360 Find Radius r 2 = x96 360 120 π ÷120x360 ÷ π r = 9.574 614 73 = 9.57 cm Hint (360÷(120x π )x96) r 120 o A=96cm 2

15. Area 14 4.5 Composite Area (1/2) Compound Areas (Add) A Triangle = 0.5 x b x h 4 m = 0.5 x 6 x 3 = 9 m 2 6 m 3 m Press A Rectangle = L x B = 6 x 4 = 24 m 2 A Total = A Triangle + A Rectangle = 9 + 24 = 33 m 2

16. Area 15 4.5 Composite Areas (2/2) Compound Areas (Minus) 6 m 10 m A Large = L x B = 10 x 6 = 60 m 2 A Total = A Large - A Small = 60 - 10 = 50 m 2 2 m 5m A Small = L x B = 5 x 2 = 10 m 2