(x+6)(2x)(x)=320

Solution for (x+6)(2x)(x)=320 equation:

(x+6)(2x)(x)=320

We move all terms to the left:

(x+6)(2x)(x)-(320)=0

We multiply parentheses

2x^2+12x-320=0

a = 2; b = 12; c = -320;
Δ = b2-4ac
Δ = 122-4·2·(-320)
Δ = 2704
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{2704}=52$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(12)-52}{2*2}=\frac{-64}{4}
=-16
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(12)+52}{2*2}=\frac{40}{4}
=10
$