This is just a little test that I can write some mathjax in this new blog:

For this I will want to use the well known formula to calculate then roots of a quadratic equation. For any $$a \ne 0$$ the equation $ax^2 +bx+c=0$ will have two solutions which can be found by

$$x = \frac{ -b \pm \sqrt{b^2 - 4ac}}{2a}$$