Greece consists of 13 administrative regions known as Peripheries of Greece, which are further subdivided into 51 prefectures (nomoi, singular - nomos):
... we get
<math>x=\frac{-b}{2a}\pm\frac{\sqrt{b^2-4ac}}{2a}=\frac{-b\pm\sqrt{b^2-4ac}}{2a}.</math>
Generalizations
The formula and its proof remain ...