x2-2x=9998

Solution for x2-2x=9998 equation:

x2-2x=9998

We move all terms to the left:

x2-2x-(9998)=0

We add all the numbers together, and all the variables

x^2-2x-9998=0

a = 1; b = -2; c = -9998;
Δ = b2-4ac
Δ = -22-4·1·(-9998)
Δ = 39996
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:

$\sqrt{\Delta}=\sqrt{39996}=\sqrt{36*1111}=\sqrt{36}*\sqrt{1111}=6\sqrt{1111}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-2)-6\sqrt{1111}}{2*1}=\frac{2-6\sqrt{1111}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-2)+6\sqrt{1111}}{2*1}=\frac{2+6\sqrt{1111}}{2}
$