It is caracterized by
External link
more on this biome (http://www.panda.org/about_wwf/where_we_work/ecoregions/global200/pages/habitat/habitat09.htm)
... solutions are also called the roots of the equation. The formula reads <math> x=\frac{-b \pm \sqrt {b^2-4ac}}{2a} </math> The term b2 – 4ac is ...