x+x*(20/100)=2500

Solution for x+x*(20/100)=2500 equation:

x+x(20/100)=2500

We move all terms to the left:

x+x(20/100)-(2500)=0

We add all the numbers together, and all the variables

x+x(+20/100)-2500=0

We multiply parentheses

20x^2+x-2500=0

a = 20; b = 1; c = -2500;
Δ = b2-4ac
Δ = 12-4·20·(-2500)
Δ = 200001
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{200001}}{2*20}=\frac{-1-\sqrt{200001}}{40}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1)+\sqrt{200001}}{2*20}=\frac{-1+\sqrt{200001}}{40}
$