-50x^2-390x-80=0

Solution for -50x^2-390x-80=0 equation:

-50x^2-390x-80=0

a = -50; b = -390; c = -80;
Δ = b2-4ac
Δ = -3902-4·(-50)·(-80)
Δ = 136100
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{136100}=\sqrt{100*1361}=\sqrt{100}*\sqrt{1361}=10\sqrt{1361}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-390)-10\sqrt{1361}}{2*-50}=\frac{390-10\sqrt{1361}}{-100}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-390)+10\sqrt{1361}}{2*-50}=\frac{390+10\sqrt{1361}}{-100}
$