(3y-2)(9+y)=0

Solution for (3y-2)(9+y)=0 equation:

(3y-2)(9+y)=0

We add all the numbers together, and all the variables

(3y-2)(y+9)=0

We multiply parentheses ..

(+3y^2+27y-2y-18)=0

We get rid of parentheses

3y^2+27y-2y-18=0

We add all the numbers together, and all the variables

3y^2+25y-18=0

a = 3; b = 25; c = -18;
Δ = b2-4ac
Δ = 252-4·3·(-18)
Δ = 841
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{841}=29$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(25)-29}{2*3}=\frac{-54}{6}
=-9
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(25)+29}{2*3}=\frac{4}{6}
=2/3
$