2x(-x+3x-8x-7)=4x-x

Solution for 2x(-x+3x-8x-7)=4x-x equation:

2x(-x+3x-8x-7)=4x-x

We move all terms to the left:

2x(-x+3x-8x-7)-(4x-x)=0

We add all the numbers together, and all the variables

2x(-6x-7)-(+3x)=0

We multiply parentheses

-12x^2-14x-(+3x)=0

We get rid of parentheses

-12x^2-14x-3x=0

We add all the numbers together, and all the variables

-12x^2-17x=0

a = -12; b = -17; c = 0;
Δ = b2-4ac
Δ = -172-4·(-12)·0
Δ = 289
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{289}=17$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-17)-17}{2*-12}=\frac{0}{-24}
=0
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-17)+17}{2*-12}=\frac{34}{-24}
=-1+5/12
$