There are a variety of modern definitions of economics, some reflect evolving views of the subject or different views among economists.
So the area of the square is 7 x7 = 49 cm^2 and the perimeter of the square is 7 x 4 = 28 cm. And in example 1 you have a square of side length 8cm and you need to work out the area and perimeter of the square. So the area of the square is 8 x8 = 64 cm^2 and the perimeter of the square is 8 x 4 = 32 cm.
1 In this case, the area within our rectangle is 4 Ã 3 = 12 square inches.  In the case of squares, since all four sides are the same, you can simply take the measurement of one side and multiply it by itself (also called squaring it or taking it to the second power) to get a square inches value for area.