0=5y^2-30y+5

Solution for 0=5y^2-30y+5 equation:

0=5y^2-30y+5

We move all terms to the left:

0-(5y^2-30y+5)=0

We add all the numbers together, and all the variables

-(5y^2-30y+5)=0

We get rid of parentheses

-5y^2+30y-5=0

a = -5; b = 30; c = -5;
Δ = b2-4ac
Δ = 302-4·(-5)·(-5)
Δ = 800
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{800}=\sqrt{400*2}=\sqrt{400}*\sqrt{2}=20\sqrt{2}$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(30)-20\sqrt{2}}{2*-5}=\frac{-30-20\sqrt{2}}{-10}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(30)+20\sqrt{2}}{2*-5}=\frac{-30+20\sqrt{2}}{-10}
$