-8x^2-54x-81=0

Solution for -8x^2-54x-81=0 equation:

-8x^2-54x-81=0

a = -8; b = -54; c = -81;
Δ = b2-4ac
Δ = -542-4·(-8)·(-81)
Δ = 324
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{324}=18$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-54)-18}{2*-8}=\frac{36}{-16}
=-2+1/4
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-54)+18}{2*-8}=\frac{72}{-16}
=-4+1/2
$