x(0.2-x)=0

Solution for x(0.2-x)=0 equation:

x(0.2-x)=0

We add all the numbers together, and all the variables

x(-1x+0.2)=0

We multiply parentheses

-1x^2+0.2x=0

a = -1; b = 0.2; c = 0;
Δ = b2-4ac
Δ = 0.22-4·(-1)·0
Δ = 0.04
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{-(0.2)-\sqrt{0.04}}{2*-1}=\frac{-0.2-\sqrt{0.04}}{-2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0.2)+\sqrt{0.04}}{2*-1}=\frac{-0.2+\sqrt{0.04}}{-2}
$