The area of a rectangle with length L and width W is given by which formula?

The area of a rectangle with length L and width W is given by which formula?

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

Answer: (B)

Area is the amount of surface a rectangle covers, so you get it by multiplying its length by its width. Think of laying out a grid of unit squares inside the rectangle: there are L units along the length and W units along the width, giving L × W unit squares in total. That product is the area, in square units (for example, if the length is 5 and the width is 3, the area is 15 square units). Other expressions don’t measure area. Adding the two sides would give a length, not an area. Doubling and adding both dimensions, 2L + 2W, gives the perimeter—the distance around the rectangle. L² + W² isn’t area either; it’s related to the diagonal via the Pythagorean theorem, since the diagonal squared equals L² + W² for a right triangle.

Area is the amount of surface a rectangle covers, so you get it by multiplying its length by its width. Think of laying out a grid of unit squares inside the rectangle: there are L units along the length and W units along the width, giving L × W unit squares in total. That product is the area, in square units (for example, if the length is 5 and the width is 3, the area is 15 square units).

Other expressions don’t measure area. Adding the two sides would give a length, not an area. Doubling and adding both dimensions, 2L + 2W, gives the perimeter—the distance around the rectangle. L² + W² isn’t area either; it’s related to the diagonal via the Pythagorean theorem, since the diagonal squared equals L² + W² for a right triangle.