X^2+2x-1920=0

Solution for X^2+2x-1920=0 equation:

X^2+2X-1920=0

a = 1; b = 2; c = -1920;
Δ = b2-4ac
Δ = 22-4·1·(-1920)
Δ = 7684
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:

$\sqrt{\Delta}=\sqrt{7684}=\sqrt{4*1921}=\sqrt{4}*\sqrt{1921}=2\sqrt{1921}$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(2)-2\sqrt{1921}}{2*1}=\frac{-2-2\sqrt{1921}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(2)+2\sqrt{1921}}{2*1}=\frac{-2+2\sqrt{1921}}{2}
$