y^2+4000=8000000

Solution for y^2+4000=8000000 equation:

y^2+4000=8000000

We move all terms to the left:

y^2+4000-(8000000)=0

We add all the numbers together, and all the variables

y^2-7996000=0

a = 1; b = 0; c = -7996000;
Δ = b2-4ac
Δ = 02-4·1·(-7996000)
Δ = 31984000
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{31984000}=\sqrt{1600*19990}=\sqrt{1600}*\sqrt{19990}=40\sqrt{19990}$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-40\sqrt{19990}}{2*1}=\frac{0-40\sqrt{19990}}{2}
=-\frac{40\sqrt{19990}}{2}
=-20\sqrt{19990}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+40\sqrt{19990}}{2*1}=\frac{0+40\sqrt{19990}}{2}
=\frac{40\sqrt{19990}}{2}
=20\sqrt{19990}
$