Equations that have more than one unknown can have an infinite number of solutions. For example, \(2x + y = 10\) could be solved by: \(x = 1\) and \(y = 8\) \(x = 2 ...

Marcus du Sautoy uses combinations of peaches and plums and a set of scales, to show how simultaneous equations can be solved. This method didn’t appear in the West until the 19th century, but had ...