1. Friday, 24 May 2019
Formulae for Finding the Area of the Rectangle, Triangle, Parallelogram and Trapezium

2. The Rectangle 3 4 Height Base Area = Base x Height A = BH Area = 4 x 3
Area = 12 square units
Area = 12 units2 3 4
Height
Base
Area = Base x Height
A = BH

3. From Rectangles to Triangles
Height
Base
Base
Notice that a rectangle contains 2 triangles
Area = Base x Height ÷ 2
A = BH ÷ 2 (or) ½ BH

4. Triangle Base Base Height Area = Base X Height ÷ 2 A = BH/2 (OR) ½BH
A = 8 X 12 ÷ 2
A = 48 cm2
Height is12cm
Base is 8 cm

5. Parallelogram
Height
Base
Area = Base x Height
A = BH

6. Height
Base

7. Trapezium b a c
Area = a x (b + c) ÷ 2