By definition, a rectangle is a two-dimensional figure that is composed of two sets of parallel and equal sides, called length and width. We know from geometry that its area is equal to the length times the width. If the problem were that simple, we only have to multiply 12 by 8. However, we only have to determine the are covered by the grass as shown in the picture.
Since there is a margin of 0.5 m on all sides, the measure of the length must be subtracted with 1 m. The 1 m accounts for 0.5 m on each of the two ends. The same is true for the width. Therefore, the area of the land covered by grass is:
Area = Length × Width
Area = (12 - 1) × (8 - 1)
Area = 77 m²
