2=-0.2x^2+1.4x

Solution for 2=-0.2x^2+1.4x equation:

2=-0.2x^2+1.4x

We move all terms to the left:

2-(-0.2x^2+1.4x)=0

We get rid of parentheses

0.2x^2-1.4x+2=0

a = 0.2; b = -1.4; c = +2;
Δ = b2-4ac
Δ = -1.42-4·0.2·2
Δ = 0.36
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{-(-1.4)-\sqrt{0.36}}{2*0.2}=\frac{1.4-\sqrt{0.36}}{0.4}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1.4)+\sqrt{0.36}}{2*0.2}=\frac{1.4+\sqrt{0.36}}{0.4}
$