0=5u^2-60

Solution for 0=5u^2-60 equation:

0=5u^2-60

We move all terms to the left:

0-(5u^2-60)=0

We add all the numbers together, and all the variables

-(5u^2-60)=0

We get rid of parentheses

-5u^2+60=0

a = -5; b = 0; c = +60;
Δ = b2-4ac
Δ = 02-4·(-5)·60
Δ = 1200
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$u_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$u_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{1200}=\sqrt{400*3}=\sqrt{400}*\sqrt{3}=20\sqrt{3}$
$u_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-20\sqrt{3}}{2*-5}=\frac{0-20\sqrt{3}}{-10}
=-\frac{20\sqrt{3}}{-10}
=-\frac{2\sqrt{3}}{-1}
$
$u_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+20\sqrt{3}}{2*-5}=\frac{0+20\sqrt{3}}{-10}
=\frac{20\sqrt{3}}{-10}
=\frac{2\sqrt{3}}{-1}
$