How is the perimeter of a rectangle calculated?

The perimeter of a rectangle is calculated by adding together the lengths of all four sides. A rectangle has two lengths and two widths. The formula to find the perimeter is derived from this concept: you multiply the length by 2 and the width by 2, which can be expressed as ( P = 2L + 2W ). This correctly sums the lengths of the opposite sides to arrive at the total distance around the rectangle.

In other options, the first option incorrectly sums just the width and height, which does not take into account both pairs of opposing sides. The second option, which uses the formula for the perimeter of a square (P = 4s), does not apply to rectangles generally, as it assumes all sides are equal. The last option mentions three sides, which suggests a triangle, not a rectangle, and therefore does not align with the properties of a rectangle. Thus, the formula ( P = 2L + 2W ) is the accurate representation of how to calculate the perimeter of a rectangle.