You can put this solution on YOUR website! First you would have to find the width since you already have the area and the length. So I would take the area of 40 feet and divide it by the length of 8 which is 5. Now that you have the length and the width you can utilize the perimeter formula which is 2(l+w) so 2(5+8)=26. The perimeter of the rug is 26 feet.