How to find the perimeter of a rectangle

2024 Author: Malcolm Clapton | [email protected]. Last modified: 2023-12-17 03:44

Four easy ways are waiting for you.

Recall that the total length of all sides is called the perimeter. It can be calculated in different ways. Choose a formula based on the data you know.

Knowing all or two adjacent sides

For completeness, we mention the simplest classical formulas.

1. If you know the length of all the sides of the rectangle, just calculate the sum of these values.
2. If you only know two adjacent sides, add them up and multiply the result by two.

• P is the required perimeter;
• a, b, c, d - sides of the rectangle.

Knowing any side and area

1. Divide the area by the length of the known side.
2. Add the result to the known side.
3. Multiply this number by two.

• P is the required perimeter of the rectangle;
• a - known side;
• S is the area of the rectangle.

Knowing any side and diagonal

1. Calculate the difference between the squares of the diagonal and the side.
2. Find the root of the result.
3. Add the resulting number to the known side.
4. Multiply the result by two.

• P is the required perimeter of the rectangle;
• a - known side;
• d is the diagonal of the rectangle.

Knowing one side and the radius of the circumscribed circle

1. Multiply the square of the radius by four.
2. Calculate the difference between the resulting number and the square of the known side.
3. Find the root of the result.
4. Add the resulting number to the known side.
5. Multiply the result by two.

• P is the required perimeter of the rectangle;
• a - known side;
• R is the radius of the circle circumscribed around the rectangle.