2(x+4)*2x=128

Solution for 2(x+4)*2x=128 equation:

2(x+4)*2x=128

We move all terms to the left:

2(x+4)*2x-(128)=0

We multiply parentheses

4x^2+16x-128=0

a = 4; b = 16; c = -128;
Δ = b2-4ac
Δ = 162-4·4·(-128)
Δ = 2304
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{2304}=48$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(16)-48}{2*4}=\frac{-64}{8}
=-8
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(16)+48}{2*4}=\frac{32}{8}
=4
$