x^2+8x=124

Solution for x^2+8x=124 equation:

x^2+8x=124

We move all terms to the left:

x^2+8x-(124)=0

a = 1; b = 8; c = -124;
Δ = b2-4ac
Δ = 82-4·1·(-124)
Δ = 560
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{560}=\sqrt{16*35}=\sqrt{16}*\sqrt{35}=4\sqrt{35}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(8)-4\sqrt{35}}{2*1}=\frac{-8-4\sqrt{35}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(8)+4\sqrt{35}}{2*1}=\frac{-8+4\sqrt{35}}{2}
$