The perimeter of a polygon (rectangle is a polygon) is the length of the line that forms it. This is, it is the sum of the length of the sides. Given that a rectangle has two pairs of equal sides the perimeter is 2 times one length plus 2 times the other length => 2*84 ft + 2*50 ft = 168 ft + 100 ft = 268 ft. <span>Answer option D. 268 feet.</span>