-5x^2-100x-320=0

Solution for -5x^2-100x-320=0 equation:

-5x^2-100x-320=0

a = -5; b = -100; c = -320;
Δ = b2-4ac
Δ = -1002-4·(-5)·(-320)
Δ = 3600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{3600}=60$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-100)-60}{2*-5}=\frac{40}{-10}
=-4
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-100)+60}{2*-5}=\frac{160}{-10}
=-16
$