16=-0.5x^2-0.1x+28.3

Solution for 16=-0.5x^2-0.1x+28.3 equation:

16=-0.5x^2-0.1x+28.3

We move all terms to the left:

16-(-0.5x^2-0.1x+28.3)=0

We get rid of parentheses

0.5x^2+0.1x-28.3+16=0

We add all the numbers together, and all the variables

0.5x^2+0.1x-12.3=0

a = 0.5; b = 0.1; c = -12.3;
Δ = b2-4ac
Δ = 0.12-4·0.5·(-12.3)
Δ = 24.61
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{-(0.1)-\sqrt{24.61}}{2*0.5}=\frac{-0.1-\sqrt{24.61}}{1}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0.1)+\sqrt{24.61}}{2*0.5}=\frac{-0.1+\sqrt{24.61}}{1}
$