What is the formula used to calculate the area of a rectangle?

The area of a rectangle is determined by multiplying its length by its width. This means that to find how much space is contained within the rectangle, you take the measurement of one side (length) and multiply it by the measurement of the other side (width). This calculation gives the total number of square units that can fit within the rectangle.

Other possible options involve addition, subtraction, or a formula for perimeter, which are not relevant for calculating area. Length plus width gives you a linear measurement rather than a space measurement. The formulation of adding both dimensions and then multiplying by 2 would provide the perimeter but not the area. Subtracting width from length does not reflect any meaningful geometric calculation relating to the area of a rectangle. Therefore, the most accurate and applicable formula for calculating the area of a rectangle is indeed the product of its length and width.