Perimeter

Definition

The perimeter is the total length around a two-dimensional shape. It is found by adding the lengths of all sides of the shape.

5 Must Know Facts For Your Next Test

1. The perimeter of a rectangle is calculated using $P = 2l + 2w$ where $l$ is length and $w$ is width.
2. For a square, the perimeter formula simplifies to $P = 4s$, where $s$ represents the length of one side.
3. When dealing with polygons, sum the lengths of all sides to find the perimeter.
4. In algebraic problems, you might need to solve for unknown side lengths using given perimeter values and equations.
5. Perimeter can be used in real-world applications such as fencing a yard or framing a picture.

Review Questions

• What is the formula for calculating the perimeter of a rectangle?
• How would you find the perimeter of an irregular polygon?
• If one side of a square measures 7 units, what is its perimeter?

Related terms

Area: The amount of space enclosed within a shape, typically measured in square units.

Polygon: A closed figure with three or more straight sides.

Equation: A mathematical statement that asserts the equality of two expressions.