There are several methods to find area and perimeter, depending on the shape of the figure. To find the area of a square or rectangle, use this formula: length x width. To find the perimeter, use this formula: (length x 2) + (width x 2).Continue Reading
Measure the length and the width of the square or rectangle. You only need to measure one side for a square, since all of the sides are equal in length.
To calculate the area, multiply the length by the width.
To find the perimeter, find the total measurement of the shape's outline. Find the sum of the lengths of all four sides of the square or rectangle. Alternatively, you can use this formula as a shortcut: (length x 2) + (width x 2).