0.2x-0.4x^2+2=0

Solution for 0.2x-0.4x^2+2=0 equation:

0.2x-0.4x^2+2=0

a = -0.4; b = 0.2; c = +2;
Δ = b2-4ac
Δ = 0.22-4·(-0.4)·2
Δ = 3.24
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{3.24}}{2*-0.4}=\frac{-0.2-\sqrt{3.24}}{-0.8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0.2)+\sqrt{3.24}}{2*-0.4}=\frac{-0.2+\sqrt{3.24}}{-0.8}
$