(2x-12)(x+1)=0

Solution for (2x-12)(x+1)=0 equation:

(2x-12)(x+1)=0

We multiply parentheses ..

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

We get rid of parentheses

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

We add all the numbers together, and all the variables

2x^2-10x-12=0

a = 2; b = -10; c = -12;
Δ = b2-4ac
Δ = -102-4·2·(-12)
Δ = 196
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{196}=14$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-10)-14}{2*2}=\frac{-4}{4}
=-1
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-10)+14}{2*2}=\frac{24}{4}
=6
$