1200=x*x

Solution for 1200=x*x equation:

1200=x*x

We move all terms to the left:

1200-(x*x)=0

We add all the numbers together, and all the variables

-(+x*x)+1200=0

We get rid of parentheses

-x*x+1200=0

Wy multiply elements

-1x^2+1200=0

a = -1; b = 0; c = +1200;
Δ = b2-4ac
Δ = 02-4·(-1)·1200
Δ = 4800
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:

$\sqrt{\Delta}=\sqrt{4800}=\sqrt{1600*3}=\sqrt{1600}*\sqrt{3}=40\sqrt{3}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-40\sqrt{3}}{2*-1}=\frac{0-40\sqrt{3}}{-2}
=-\frac{40\sqrt{3}}{-2}
=-\frac{20\sqrt{3}}{-1}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+40\sqrt{3}}{2*-1}=\frac{0+40\sqrt{3}}{-2}
=\frac{40\sqrt{3}}{-2}
=\frac{20\sqrt{3}}{-1}
$