y^2+8y-155=0

Solution for y^2+8y-155=0 equation:

y^2+8y-155=0

a = 1; b = 8; c = -155;
Δ = b2-4ac
Δ = 82-4·1·(-155)
Δ = 684
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:

$\sqrt{\Delta}=\sqrt{684}=\sqrt{36*19}=\sqrt{36}*\sqrt{19}=6\sqrt{19}$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(8)-6\sqrt{19}}{2*1}=\frac{-8-6\sqrt{19}}{2}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(8)+6\sqrt{19}}{2*1}=\frac{-8+6\sqrt{19}}{2}
$