y(y-6)=-6

Solution for y(y-6)=-6 equation:

y(y-6)=-6

We move all terms to the left:

y(y-6)-(-6)=0

We add all the numbers together, and all the variables

y(y-6)+6=0

We multiply parentheses

y^2-6y+6=0

a = 1; b = -6; c = +6;
Δ = b2-4ac
Δ = -62-4·1·6
Δ = 12
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:

$\sqrt{\Delta}=\sqrt{12}=\sqrt{4*3}=\sqrt{4}*\sqrt{3}=2\sqrt{3}$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-6)-2\sqrt{3}}{2*1}=\frac{6-2\sqrt{3}}{2}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-6)+2\sqrt{3}}{2*1}=\frac{6+2\sqrt{3}}{2}
$