6. AREA OF TRAPEZIUM = ½ x ( a + b ) x h 4 cm 6 cm 5 cm F Area of F = ½ x ( 4 cm + 6 cm ) x 5 cm = ½ x 10 cm x 5 cm = 25 cm²
7. To find areas of figures made up of trianges, rectangles, parallelograms or trapeziums Example 1 Area of triangle = ½ x 8cm x 6 cm = ½ x 48cm² = 24 cm² Solution Area of square = 4 cm x 4 cm = 16 cm² 4 cm 8 cm 4 cm Area of the figure = 24cm² + 16 cm² = 40 cm²
8. Example 2 7m 4m Area of rectangle = 7m x 4m = 28 m² Area of triangle = ½ x 7m x 6 m = ½ x 42 m² = 21 m² Area of the figure = 28 m² +21 m² = 49 m² 6 m
9. Example 3 A B C Area of A = ½ x 3 m x 3 m = ½ x 9 m² = 4.5 m² Area of B = 10 m x 3 m = 30 m² Area of C = ½ x 3 m x 3 m = ½ x 9 m² = 4.5 m² Area of the figure = (4.5 m² + 30 m²) + 4.5 m² = 34.5 m² 4.5 m² = 39 m² 10 m 3 m
10. Example 4 Area of D = ½ x (6 cm + 8 cm) x 7 cm = 49 cm² Area of E = ½ x 5 cm x 8 cm = ½ x 40 cm² = 20 cm² Area of the figure = 49 cm² + 20 cm² = 69 cm² E 8 cm D 5 cm 6 cm 7 cm