-0.1x^2+0.6x-0.4=0

Solution for -0.1x^2+0.6x-0.4=0 equation:

-0.1x^2+0.6x-0.4=0

a = -0.1; b = 0.6; c = -0.4;
Δ = b2-4ac
Δ = 0.62-4·(-0.1)·(-0.4)
Δ = 0.2
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{-(0.6)-\sqrt{0.2}}{2*-0.1}=\frac{-0.6-\sqrt{0.2}}{-0.2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0.6)+\sqrt{0.2}}{2*-0.1}=\frac{-0.6+\sqrt{0.2}}{-0.2}
$