-2x^2-13x-18=0

Solution for -2x^2-13x-18=0 equation:

-2x^2-13x-18=0

a = -2; b = -13; c = -18;
Δ = b2-4ac
Δ = -132-4·(-2)·(-18)
Δ = 25
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{25}=5$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-13)-5}{2*-2}=\frac{8}{-4}
=-2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-13)+5}{2*-2}=\frac{18}{-4}
=-4+1/2
$