Perimeter of the rectangular area = 2 (Length + Breadth) = 6 km = (L + B) = 3 km Area of the rectangular area = Length × Breadth = 2 sq. km = L × B = 2 sq. km We know, (a+b)2–(a–b)2 = 4 ab Suppose, L = a and B = b Therefore, (3)2–(a–b)2 = 4 × 2 ⇒ (a–b)2 = 9 – 8 ⇒ a – b = 1 Difference between Length and Breadth = 1 km