y2+30y+221=0

Solution for y2+30y+221=0 equation:

y2+30y+221=0

We add all the numbers together, and all the variables

y^2+30y+221=0

a = 1; b = 30; c = +221;
Δ = b2-4ac
Δ = 302-4·1·221
Δ = 16
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{16}=4$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(30)-4}{2*1}=\frac{-34}{2}
=-17
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(30)+4}{2*1}=\frac{-26}{2}
=-13
$