X2-2x=440

Solution for X2-2x=440 equation:

X2-2X=440

We move all terms to the left:

X2-2X-(440)=0

We add all the numbers together, and all the variables

X^2-2X-440=0

a = 1; b = -2; c = -440;
Δ = b2-4ac
Δ = -22-4·1·(-440)
Δ = 1764
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1764}=42$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-2)-42}{2*1}=\frac{-40}{2}
=-20
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-2)+42}{2*1}=\frac{44}{2}
=22
$