(20x-20)(12x+8)=0

Solution for (20x-20)(12x+8)=0 equation:

(20x-20)(12x+8)=0

We multiply parentheses ..

(+240x^2+160x-240x-160)=0

We get rid of parentheses

240x^2+160x-240x-160=0

We add all the numbers together, and all the variables

240x^2-80x-160=0

a = 240; b = -80; c = -160;
Δ = b2-4ac
Δ = -802-4·240·(-160)
Δ = 160000
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{160000}=400$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-80)-400}{2*240}=\frac{-320}{480}
=-2/3
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-80)+400}{2*240}=\frac{480}{480}
=1
$