x+x(18/100)-11800=0

Solution for x+x(18/100)-11800=0 equation:

x+x(18/100)-11800=0

We add all the numbers together, and all the variables

x+x(+18/100)-11800=0

We multiply parentheses

18x^2+x-11800=0

a = 18; b = 1; c = -11800;
Δ = b2-4ac
Δ = 12-4·18·(-11800)
Δ = 849601
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{-(1)-\sqrt{849601}}{2*18}=\frac{-1-\sqrt{849601}}{36}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1)+\sqrt{849601}}{2*18}=\frac{-1+\sqrt{849601}}{36}
$