Income tax is a direct tax which is levied on the income of private individuals. Various income tax systems exist. Those range from a flat tax to an extensive progressive tax[?] system.
Taxes levied on the income of companies is called corporate tax[?].
... from both sides, 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 ...