That's always been the case, and perhaps always will be. From 2-D to 3-D An early attempt to explain the concept of extra dimensions came in 1884 with the publication of Edwin A. Abbott's Flatland ...

Number × Length = Length (one dimension) Number × Area = Area (two dimensions) Number × Volume = Volume (three dimensions) Length × Length = Area (two dimensions) Length × Length × Length ...

The diagram shows a rectangle. The length of the rectangle is \(2x + 5\). The width of the rectangle is \(3x - 2\). The highlighted words are the most important ones. The key word in the question ...