-2x^2-28x=80

Solution for -2x^2-28x=80 equation:

-2x^2-28x=80

We move all terms to the left:

-2x^2-28x-(80)=0

a = -2; b = -28; c = -80;
Δ = b2-4ac
Δ = -282-4·(-2)·(-80)
Δ = 144
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{144}=12$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-28)-12}{2*-2}=\frac{16}{-4}
=-4
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-28)+12}{2*-2}=\frac{40}{-4}
=-10
$