(20,000-300x)(12+2x)=0

Solution for (20,000-300x)(12+2x)=0 equation:

(20.000-300x)(12+2x)=0

We add all the numbers together, and all the variables

(-300x+20)(2x+12)=0

We multiply parentheses ..

(-600x^2-3600x+40x+240)=0

We get rid of parentheses

-600x^2-3600x+40x+240=0

We add all the numbers together, and all the variables

-600x^2-3560x+240=0

a = -600; b = -3560; c = +240;
Δ = b2-4ac
Δ = -35602-4·(-600)·240
Δ = 13249600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{13249600}=3640$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-3560)-3640}{2*-600}=\frac{-80}{-1200}
=1/15
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-3560)+3640}{2*-600}=\frac{7200}{-1200}
=-6
$