### Theory:

Now, we shall find the perimeter of a square.

Let $$ABCD$$ be a square with sides of length $$a$$ $$units$$.

Then, the perimeter of the square $$ABCD$$ is given by:
Perimeter of the square $$=$$ Sum of the measures of all four sides
Perimeter, $$P =AB+BC+CD+DA$$ $$units$$

$$P=a+a+a+a$$ $$units$$

$$P=4a$$ $$units$$

Thus, the perimeter of the square is $$4a$$ $$units$$.
Example:
1. Let the side of a square be $$8 \ cm$$. Find the perimeter of the square.

Solution:

Side of a square, $$a=8 \ cm$$.

Perimeter of the square $$=$$ Sum of the measures of all four sides

Substituting the values in the formula, we have:

Perimeter, $$P=4a$$

$$P=4\times 8 \ cm$$

$$P=32 \ cm$$

Thus, the perimeter of the square is $$32 \ cm$$.