-2x-9+12x2=0

Solution for -2x-9+12x2=0 equation:

-2x-9+12x^2=0

a = 12; b = -2; c = -9;
Δ = b2-4ac
Δ = -22-4·12·(-9)
Δ = 436
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{436}=\sqrt{4*109}=\sqrt{4}*\sqrt{109}=2\sqrt{109}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-2)-2\sqrt{109}}{2*12}=\frac{2-2\sqrt{109}}{24}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-2)+2\sqrt{109}}{2*12}=\frac{2+2\sqrt{109}}{24}
$