Area = 338 square feet
Width (y) = 1/2 the length = 1/2*x, where x is the length of the fencing.
The area of the rectangle is A = xy.
(x/2)(x) = 338 ⇒ x2/2 = 338
Solve for x.
x2 = 676 ⇒ x = ± 26 (negative solution doesn't exist)
We need 26 feet of fencing for the rectangular yard.