9x^2+12x+4=121

Solution for 9x^2+12x+4=121 equation:

9x^2+12x+4=121

We move all terms to the left:

9x^2+12x+4-(121)=0

We add all the numbers together, and all the variables

9x^2+12x-117=0

a = 9; b = 12; c = -117;
Δ = b2-4ac
Δ = 122-4·9·(-117)
Δ = 4356
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{4356}=66$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(12)-66}{2*9}=\frac{-78}{18}
=-4+1/3
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(12)+66}{2*9}=\frac{54}{18}
=3
$