X+20/100xx=18

Solution for X+20/100xx=18 equation:

X+20/100XX=18

We move all terms to the left:

X+20/100XX-(18)=0


Domain of the equation: 100XX!=0

X!=0/1

X!=0

X∈R


We multiply all the terms by the denominator


X*100XX-18*100XX+20=0

Wy multiply elements

100X^2-1800X+20=0

a = 100; b = -1800; c = +20;
Δ = b2-4ac
Δ = -18002-4·100·20
Δ = 3232000
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{3232000}=\sqrt{6400*505}=\sqrt{6400}*\sqrt{505}=80\sqrt{505}$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-1800)-80\sqrt{505}}{2*100}=\frac{1800-80\sqrt{505}}{200}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1800)+80\sqrt{505}}{2*100}=\frac{1800+80\sqrt{505}}{200}
$