12x^2-12x-864=0

Solution for 12x^2-12x-864=0 equation:

12x^2-12x-864=0

a = 12; b = -12; c = -864;
Δ = b2-4ac
Δ = -122-4·12·(-864)
Δ = 41616
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{41616}=204$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-12)-204}{2*12}=\frac{-192}{24}
=-8
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-12)+204}{2*12}=\frac{216}{24}
=9
$