How to Determine the Perimeter of Given Plane Figures - JSS1 Mathematics Lesson Note

To find the perimeter of a shape, you typically add together the lengths of all its sides. Here are examples for both irregular and regular shapes:

Regular Shapes Example (Square):

Square: Suppose we have a square with each side measuring 5 cm.

To find the perimeter, add up all four sides: 

5 cm+5 cm+5 cm+ cm=20 cm.

Therefore, the perimeter of the square is 

20cm.

Irregular Shapes Example (Rectangular Garden):

Rectangle (Irregular): Imagine a garden in the shape of a rectangle, where the lengths of the sides are 10 meters and 15 meters.

To determine the perimeter, add the lengths of all sides: 

10 m+15 m+10 m+15 m=50 m.

Thus, the perimeter of the rectangular garden is 50 m.