1.8=x2

Solution for 1.8=x2 equation:

1.8=x2

We move all terms to the left:

1.8-(x2)=0

We add all the numbers together, and all the variables

-1x^2+1.8=0

a = -1; b = 0; c = +1.8;
Δ = b2-4ac
Δ = 02-4·(-1)·1.8
Δ = 7.2
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-\sqrt{7.2}}{2*-1}=\frac{0-\sqrt{7.2}}{-2}
=-\frac{\sqrt{}}{-2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+\sqrt{7.2}}{2*-1}=\frac{0+\sqrt{7.2}}{-2}
=\frac{\sqrt{}}{-2}
$