(6x+18)(3x-2)=0

Solution for (6x+18)(3x-2)=0 equation:

(6x+18)(3x-2)=0

We multiply parentheses ..

(+18x^2-12x+54x-36)=0

We get rid of parentheses

18x^2-12x+54x-36=0

We add all the numbers together, and all the variables

18x^2+42x-36=0

a = 18; b = 42; c = -36;
Δ = b2-4ac
Δ = 422-4·18·(-36)
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{-(42)-66}{2*18}=\frac{-108}{36}
=-3
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(42)+66}{2*18}=\frac{24}{36}
=2/3
$