The perimeter of a rectangle is the sum of the length of all four sides. Alternate formulas for finding the perimeter are 2(length + width) and 2 x length + 2 x width.
A rectangle is a four-sided figure containing four right angles and two pairs of parallel sides. The area of a rectangle is determined by multiplying the length times the width. For example, if a rectangle is 7 inches long by 5 inches wide, find the perimeter by adding 7 inches + 5 inches and multiplying the sum by 2. The result is a perimeter of 24 inches. To find the area of the rectangle, multiply 7 inches by 5 inches, for a total of 35 square inches.