**Definition of Boundary**

- Boundary is a border that encloses a space or an area.

- The distance around the boundary is called as ‘perimeter’.

- The length of the three sides of a triangular field is 9 m, 5 m, and 11 m.

The boundary or perimeter of the field is given as 9 m + 5 m + 11 m = 25 m.

**Solved Example on Boundary**

A gardener wants to plant 4 plants per meter along the boundary of a garden, which is represented by the quadrilateral ABCD shown in the figure. Calculate the number of plants required.

Choices:

A. 75

B. 80

C. 70

D. 60

Correct Answer: B

Solution:

Step 1:Perimeter of the quadrilateral ABCD = Sum of the four sides of the quadrilateral.

Step 2:= AB + BC + CD + DA

Step 3:= 3 + 8 + 4 + 5 = 20 meters [Substitute AB = 3, BC = 8, CD = 4, and DA = 5 and simplify.]

Step 4:The number of plants required = 20 × 4 = 80.

**Related Terms for Boundary**

- Area
- Distance
- Perimeter