Since we have 3 sides (that are W, L and W units long), the perimeter of the garden (excluding the barn wall) is... W+L+W = 2W+L So the length of fencing needed is 2W + L feet. But we're given that we have 100 ft of fencing. So if we use every bit of that fencing, we know that 2W + L = 100 Solve for L: 2W + L = 100 2W + L -2W = 100 - 2W L = 100 - 2W ------------------------------------------------------- Now onto the area of this garden.The area of any rectangle is just the result of multiplying the length by the width. So A = LW