(x)(x)(2x-60)=60

Solution for (x)(x)(2x-60)=60 equation:

(x)(x)(2x-60)=60

We move all terms to the left:

(x)(x)(2x-60)-(60)=0

We multiply parentheses

2x^2-60x-60=0

a = 2; b = -60; c = -60;
Δ = b2-4ac
Δ = -602-4·2·(-60)
Δ = 4080
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:

$\sqrt{\Delta}=\sqrt{4080}=\sqrt{16*255}=\sqrt{16}*\sqrt{255}=4\sqrt{255}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-60)-4\sqrt{255}}{2*2}=\frac{60-4\sqrt{255}}{4}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-60)+4\sqrt{255}}{2*2}=\frac{60+4\sqrt{255}}{4}
$