Perimeter of a rectangle
Perimeter P = 2 x (w + h)

AB = DC = width = w
AD = BC = h = height

Example

ABCD is a rectangle of width w = 8 cm and of height h = 4 cm
Perimeter P of the rectangle = 2 x (w + h) = 2 x (8 + 4) = 2 x 12 = 24 cm

Calculate the perimeter of a rectangle

Width
Height
Perimeter of the rectangle