1800=2n*n

Solution for 1800=2n*n equation:

1800=2n*n

We move all terms to the left:

1800-(2n*n)=0

We add all the numbers together, and all the variables

-(+2n*n)+1800=0

We get rid of parentheses

-2n*n+1800=0

Wy multiply elements

-2n^2+1800=0

a = -2; b = 0; c = +1800;
Δ = b2-4ac
Δ = 02-4·(-2)·1800
Δ = 14400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{14400}=120$
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-120}{2*-2}=\frac{-120}{-4}
=+30
$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+120}{2*-2}=\frac{120}{-4}
=-30
$