X^2+2x=3960

Solution for X^2+2x=3960 equation:

X^2+2X=3960

We move all terms to the left:

X^2+2X-(3960)=0

a = 1; b = 2; c = -3960;
Δ = b2-4ac
Δ = 22-4·1·(-3960)
Δ = 15844
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:

$\sqrt{\Delta}=\sqrt{15844}=\sqrt{4*3961}=\sqrt{4}*\sqrt{3961}=2\sqrt{3961}$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(2)-2\sqrt{3961}}{2*1}=\frac{-2-2\sqrt{3961}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(2)+2\sqrt{3961}}{2*1}=\frac{-2+2\sqrt{3961}}{2}
$