x^2=9999

Solution for x^2=9999 equation:

x^2=9999

We move all terms to the left:

x^2-(9999)=0

a = 1; b = 0; c = -9999;
Δ = b2-4ac
Δ = 02-4·1·(-9999)
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{-(0)-6\sqrt{1111}}{2*1}=\frac{0-6\sqrt{1111}}{2}
=-\frac{6\sqrt{1111}}{2}
=-3\sqrt{1111}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+6\sqrt{1111}}{2*1}=\frac{0+6\sqrt{1111}}{2}
=\frac{6\sqrt{1111}}{2}
=3\sqrt{1111}
$