Perimeter of a rectangle

The perimeter of a rectangle is the sum of the lengths of all four sides of the rectangle. A rectangle always has two and two sides of equal length; if all four sides are equal, it is a square. Denote the lengths of the two different sides by a and b. Then the perimeter of the rectangle, denoted by o, is equal to

$$\Large o = 2 \cdot a + 2 \cdot b$$

The following rectangle has side lengths equal to a = 5, b = 2, so the perimeter of the rectangle will be equal to

$$\Large o = 2\cdot 5 + 2\cdot 2 = 14$$