The perimeter of a quadrilateral is the sum of the length of all four sides. In a square, each side is of equal length. Thus, the perimeter is the length of a side (given) times 4.

If the area of a square is , then the length of one side will be equal to the square root of . 

The perimeter is equal to 4 times the length of one side. 

This gives us: 

One of your holiday gifts is wrapped in a cube-shaped box. 

If one of the edges has a length of 6 inches, what is the perimeter of one side of the box? 

To find perimeter of a square, simply multiply the side length by 4

Call the diameter of the circle . The length of each side of the square also is equal to this.

The diameter of the circle is equal to its circumference divided by , so

.

The perimeter of the square is four times this sidelength, so 

.

To find the perimeter of a square, we will use the following formula:

where a, b, c, and d are the lengths of the sides of the square.

Now, we know the width of the square has a length of 4cm.  Because it is a square, all sides are equal.  Therefore, all sides are 4cm.

Knowing this, we can substitute into the formula.  We get

While out walking, you find a strange, square-shaped piece of metal. If the side length of the piece is 26 inches, what is the perimeter of the square?

To find the perimeter of a square, simply multiply the side length by 4. We can do this because perimeter is the distance around the outside of a shape, and squares have 4 equal sides.

To find the perimeter of a square, we will use the following formula:

where a, b, c, and d are the lengths of the sides of the square.

Now, we know the width of the square is 18in. Because it is a square, all sides are equal. Therefore, all sides are 18in.

So, we get

A square has 4 equal sides.

Write the formula for the perimeter of a square.

Substitute the side length.

Evaluate the terms on the right.

The answer is:  

Your new friend has a very small, square-shaped dorm room. She tells you that it is only 225 square feet. Assuming this is true, what is the perimeter of her room?

So, we need to find the perimeter of a square. First, we need to find the side length.

Let's begin with our formula for the area of a square:

where s is our side length and A is our area.

With this formula, we can solve for our side length by plugging in our area and square rooting both sides.

Now, we are close but not quite done. We need to multiply our side length by 4, because a square always has 4 equal sides.

The area decreases by 20% of 20%, which is 4%.

The easiest way to see this is to plug in numbers for the sides of the square.  If we are using percentages, it is easiest to use factors of 10 or 100.  In this case we will say that the square has a side length of 10.

10% of 10 is 1, so 20% is 2.  Now we can just increase one of the sides by 2, and decrease another side by 2.  So our rectangle has dimensions of 12 x 8 instead of 10 x 10.  

The original square had an area of 100, and the new rectangle has an area of 96. So the rectangle is 4 square units smaller, which is 4% smaller than the original square.