12b^2-12b-9=0

Solution for 12b^2-12b-9=0 equation:

12b^2-12b-9=0

a = 12; b = -12; c = -9;
Δ = b2-4ac
Δ = -122-4·12·(-9)
Δ = 576
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{576}=24$
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-12)-24}{2*12}=\frac{-12}{24}
=-1/2
$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-12)+24}{2*12}=\frac{36}{24}
=1+1/2
$