0=-0.2x^2+2x

Solution for 0=-0.2x^2+2x equation:

0=-0.2x^2+2x

We move all terms to the left:

0-(-0.2x^2+2x)=0

We add all the numbers together, and all the variables

-(-0.2x^2+2x)=0

We get rid of parentheses

0.2x^2-2x=0

a = 0.2; b = -2; c = 0;
Δ = b2-4ac
Δ = -22-4·0.2·0
Δ = 4
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{4}=2$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-2)-2}{2*0.2}=\frac{0}{0.4}
=0
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-2)+2}{2*0.2}=\frac{4}{0.4}
=10
$