5(y+20)y=-2

Solution for 5(y+20)y=-2 equation:

5(y+20)y=-2

We move all terms to the left:

5(y+20)y-(-2)=0

We add all the numbers together, and all the variables

5(y+20)y+2=0

We multiply parentheses

5y^2+100y+2=0

a = 5; b = 100; c = +2;
Δ = b2-4ac
Δ = 1002-4·5·2
Δ = 9960
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:

$\sqrt{\Delta}=\sqrt{9960}=\sqrt{4*2490}=\sqrt{4}*\sqrt{2490}=2\sqrt{2490}$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(100)-2\sqrt{2490}}{2*5}=\frac{-100-2\sqrt{2490}}{10}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(100)+2\sqrt{2490}}{2*5}=\frac{-100+2\sqrt{2490}}{10}
$