Page 2 - LN 6.1

 PERIMETER: 4a

 EXAMPLE: Find the distance travelled by Usha if she takes three rounds
of a square park of side 75 m.
SOLUTION: First, we need to find the perimeter of the square.

Perimeter of the square park = 4 × length of a side = 4 × 75 m = 300 m.
She took three rounds, therefore, the total distance travelled by Usha in
three rounds = 3 × 300 m = 900 m.

 PERIMETER OF A TRIANGLE: Perimeter of a triangle = sum of the lengths
of its three sides.

 Perimeter of the triangle = 4 cm + 5 cm + 7 cm = 16 cm.

 PERIMETER OF A REGULAR POLYGON:
RECALL: Closed figures that have all sides and all angles equal are called
regular polygons.

 Perimeter of an equilateral triangle = AB + BC + AC = AB + AB + AB
= 3 times length of one side.
 Perimeter of an equilateral triangle = 3 × length of a side.

 Perimeter of n sided regular polygon = n× length of one side.