-5y(-30-10y)=0

Solution for -5y(-30-10y)=0 equation:

-5y(-30-10y)=0

We add all the numbers together, and all the variables

-5y(-10y-30)=0

We multiply parentheses

50y^2+150y=0

a = 50; b = 150; c = 0;
Δ = b2-4ac
Δ = 1502-4·50·0
Δ = 22500
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{22500}=150$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(150)-150}{2*50}=\frac{-300}{100}
=-3
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(150)+150}{2*50}=\frac{0}{100}
=0
$