A = W· L 10,000 = W ( W +30 ) = W² + 30 W W² + 30 W - 10,000 = 0 W = [tex] \frac{-30+ \sqrt{900+40000} }{2}= \frac{-30+202.24}{2} = 86.12 [/tex] L = 86.12 + 30 = 116.12 Width of a plot is 86.12 m and lenght is 116.12 m. Check : A = 116.12 · 86.12 ≈ 10,000