x(x-4)(X+4)=600

Solution for x(x-4)(X+4)=600 equation:

x(x-4)(x+4)=600

We move all terms to the left:

x(x-4)(x+4)-(600)=0

We use the square of the difference formula

x^2-16-600=0

We add all the numbers together, and all the variables

x^2-616=0

a = 1; b = 0; c = -616;
Δ = b2-4ac
Δ = 02-4·1·(-616)
Δ = 2464
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{2464}=\sqrt{16*154}=\sqrt{16}*\sqrt{154}=4\sqrt{154}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-4\sqrt{154}}{2*1}=\frac{0-4\sqrt{154}}{2}
=-\frac{4\sqrt{154}}{2}
=-2\sqrt{154}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+4\sqrt{154}}{2*1}=\frac{0+4\sqrt{154}}{2}
=\frac{4\sqrt{154}}{2}
=2\sqrt{154}
$