-4x(8-3x)=112

Solution for -4x(8-3x)=112 equation:

-4x(8-3x)=112

We move all terms to the left:

-4x(8-3x)-(112)=0

We add all the numbers together, and all the variables

-4x(-3x+8)-112=0

We multiply parentheses

12x^2-32x-112=0

a = 12; b = -32; c = -112;
Δ = b2-4ac
Δ = -322-4·12·(-112)
Δ = 6400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{6400}=80$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-32)-80}{2*12}=\frac{-48}{24}
=-2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-32)+80}{2*12}=\frac{112}{24}
=4+2/3
$