-8g^2-400g-1800=0

Solution for -8g^2-400g-1800=0 equation:

-8g^2-400g-1800=0

a = -8; b = -400; c = -1800;
Δ = b2-4ac
Δ = -4002-4·(-8)·(-1800)
Δ = 102400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$g_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$g_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{102400}=320$
$g_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-400)-320}{2*-8}=\frac{80}{-16}
=-5
$
$g_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-400)+320}{2*-8}=\frac{720}{-16}
=-45
$