When the height of a cuboid increases by 2cm, it becomes a cube. At this time, the surface area increases by 56 square centimeters. What is the volume of the original cuboid? Attach the formula and explanation

When the height of a cuboid increases by 2cm, it becomes a cube. At this time, the surface area increases by 56 square centimeters. What is the volume of the original cuboid? Attach the formula and explanation

The surface area is increased by side area = 4 × side length × 2 = 56 square centimeter
Side length = 56 △ 8 = 7 cm
The volume of the original cuboid is 7 × 7 × (7-2) = 245 cubic centimeters