What is the formula for the perimeter of a rectangle?

• A. P = l + w
• B. P = 2(l + w)
• C. P = lw
• D. P = 2lw

Answer: (B)

The perimeter of a rectangle is calculated using the formula that incorporates both the length and the width. Specifically, to find the total distance around the rectangle, you add the lengths of all four sides. Since a rectangle has two lengths and two widths, the formula is expressed as P = 2(l + w). This effectively means you are calculating the sum of the lengths and widths and then multiplying that sum by 2 to account for both pairs of sides.

The option that states the perimeter as P = l + w only gives the sum of one length and one width, which does not account for the full perimeter of the rectangle. Similarly, the formulas involving lw either describe the area of the rectangle (P = lw) or would not correctly represent the perimeter (P = 2lw). Thus, using P = 2(l + w) correctly provides the total distance around the rectangle, ensuring both dimensions are included in the calculation.