Unit of measure of surface that is equivalent to the area of a square with sides that are each one kilometre long.
Notation
We write: 1 km\(^{2}\) = 1 000 000 m\(^{2}\), because 1000 × 1000 = 1 000 000.
We write: 1 km\(^{2}\) = 1 000 000 m\(^{2}\), because 1000 × 1000 = 1 000 000.