Which expression correctly represents the perimeter of a rectangle with length L and width W?

• A. P = L + W
• B. P = 2L + 2W
• C. P = 2L
• D. P = L^2 + W^2

Answer: (B)

Perimeter is the distance around a shape. For a rectangle, opposite sides are equal, so there are two sides of length L and two sides of width W. Adding all four sides gives L + L + W + W, which simplifies to 2L + 2W, or 2(L + W). This expression correctly represents the perimeter.

For comparison, adding just L + W would cover only two sides, not the full outline. Using 2L would account for only the two longer sides, missing the widths. L^2 + W^2 isn’t a perimeter at all; it relates to other quantities like the diagonal (Pythagoras) or area confusion, not the distance around the rectangle.