(-6x-3)(-2x+4)=0

Solution for (-6x-3)(-2x+4)=0 equation:

(-6x-3)(-2x+4)=0

We multiply parentheses ..

(+12x^2-24x+6x-12)=0

We get rid of parentheses

12x^2-24x+6x-12=0

We add all the numbers together, and all the variables

12x^2-18x-12=0

a = 12; b = -18; c = -12;
Δ = b2-4ac
Δ = -182-4·12·(-12)
Δ = 900
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{900}=30$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-18)-30}{2*12}=\frac{-12}{24}
=-1/2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-18)+30}{2*12}=\frac{48}{24}
=2
$