I'm new to Quadratic Equations and I am following the two formulas to find $x_1$ and $x_2$ and they are:
$\Delta = b^2 - 4ac$
$x = \dfrac{-(b) \pm \sqrt\Delta}{2a}$
but delta always gives a negative number;
for example I have the following equation:
$6x^2 + 11x - 35 = 0$
What I did was:
1. Calculate the Delta ($\Delta$) by using the formula above $11^2 - 4ac$
$11^2 = 121$ and $4ac = -840 = 4\times6\times(-35)$
$\Delta = 121 - 840 = 719$
and got $-719$ as result