18,04=x^2+6x

Solution for 18,04=x^2+6x equation:

18.04=x^2+6x

We move all terms to the left:

18.04-(x^2+6x)=0

We get rid of parentheses

-x^2-6x+18.04=0

We add all the numbers together, and all the variables

-1x^2-6x+18.04=0

a = -1; b = -6; c = +18.04;
Δ = b2-4ac
Δ = -62-4·(-1)·18.04
Δ = 108.16
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{-(-6)-\sqrt{108.16}}{2*-1}=\frac{6-\sqrt{108.16}}{-2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-6)+\sqrt{108.16}}{2*-1}=\frac{6+\sqrt{108.16}}{-2}
$