x^2+20x=76

Solution for x^2+20x=76 equation:

x^2+20x=76

We move all terms to the left:

x^2+20x-(76)=0

a = 1; b = 20; c = -76;
Δ = b2-4ac
Δ = 202-4·1·(-76)
Δ = 704
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:

$\sqrt{\Delta}=\sqrt{704}=\sqrt{64*11}=\sqrt{64}*\sqrt{11}=8\sqrt{11}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(20)-8\sqrt{11}}{2*1}=\frac{-20-8\sqrt{11}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(20)+8\sqrt{11}}{2*1}=\frac{-20+8\sqrt{11}}{2}
$