9x2+6x+12x+8=0

Solution for 9x2+6x+12x+8=0 equation:

9x^2+6x+12x+8=0

We add all the numbers together, and all the variables

9x^2+18x+8=0

a = 9; b = 18; c = +8;
Δ = b2-4ac
Δ = 182-4·9·8
Δ = 36
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{36}=6$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(18)-6}{2*9}=\frac{-24}{18}
=-1+1/3
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(18)+6}{2*9}=\frac{-12}{18}
=-2/3
$