9y*y+12y-12=0

Solution for 9y*y+12y-12=0 equation:

9y*y+12y-12=0

We add all the numbers together, and all the variables

12y+9y*y-12=0

Wy multiply elements

9y^2+12y-12=0

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

$\sqrt{\Delta}=\sqrt{576}=24$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(12)-24}{2*9}=\frac{-36}{18}
=-2
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(12)+24}{2*9}=\frac{12}{18}
=2/3
$