-0,1x^2+0,6x+7,2=0

Solution for -0,1x^2+0,6x+7,2=0 equation:

-0.1x^2+0.6x+7.2=0

a = -0.1; b = 0.6; c = +7.2;
Δ = b2-4ac
Δ = 0.62-4·(-0.1)·7.2
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{-(0.6)-\sqrt{3.24}}{2*-0.1}=\frac{-0.6-\sqrt{3.24}}{-0.2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0.6)+\sqrt{3.24}}{2*-0.1}=\frac{-0.6+\sqrt{3.24}}{-0.2}
$