What is the formula to calculate the perimeter of a rectangle?

The formula to calculate the perimeter of a rectangle is defined by the sum of all its sides. A rectangle has two lengths and two widths, which are usually referred to as 'l' for length and 'w' for width. Therefore, the perimeter is calculated by adding the lengths of all sides together:

P = l + w + l + w, which can be simplified to P = 2l + 2w, or factoring out the 2 gives P = 2(l + w).

This formula shows that the perimeter is directly related to both the length and width of the rectangle, making it clear how each dimension contributes to the total distance around the shape.

The other formulas provided do not correctly represent the perimeter of a rectangle. The product of length and width is used to calculate the area, not the perimeter. Simply adding the length and width does not account for the fact that there are two of each in a rectangle; thus, it provides only half of what is needed.