(-0.5x^2)+1.15x+(-0.1)=0

Solution for (-0.5x^2)+1.15x+(-0.1)=0 equation:

(-0.5x^2)+1.15x+(-0.1)=0

We add all the numbers together, and all the variables

(-0.5x^2)+1.15x-0.1=0

We get rid of parentheses

-0.5x^2+1.15x-0.1=0

a = -0.5; b = 1.15; c = -0.1;
Δ = b2-4ac
Δ = 1.152-4·(-0.5)·(-0.1)
Δ = 1.1225
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{-(1.15)-\sqrt{1.1225}}{2*-0.5}=\frac{-1.15-\sqrt{1.1225}}{-1}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1.15)+\sqrt{1.1225}}{2*-0.5}=\frac{-1.15+\sqrt{1.1225}}{-1}
$