Area and Perimeter of Composite figures

After completing activities Review the formulas for Perimeter and Area of basic shapes on the next slides View the animated worked example on the following slides

Formulas for basic Quadrilaterals

Example 1 Find the area of the figure below 15 cm 50 cm

15 cm = cm Triangle Rectangle Square 20cm15 cm 30 cm Area = Height × base 2 Area = 30 × 20 Area = Rectangle: Area = Length × width Area =30 × 15 Area = Square : Area = (side) 2 Area =(15) 2 Area = 300 cm cm cm 2 2 Triangle : Total area = = 975 cm 2

What is the area of the window shown? Use ( π =3.14 ) Example 2 48 in 36 in

48 in 36 in + 48 in =

36 in = + 48 in Rectangle : Area = 36 × 48 Area = 1728 in 2 Half of circle : Area = Area = in × (18) 2 2 Area = in in 2 Total area = = in 2

8cm 6cm 8cm 12cm Example 3

8cm 6cm 8cm 12cm + 4cm -

8cm 6cm 8cm 12cm + 4cm - Total Area = – 8 = 128 cm 2 A = 8 cm 2 A = 96 cm 2

Mr. Ali Abdalla Abdelmohsen Mahmoud EGYPT – Asyut UAE – Abu Dhabi