0=0.08s^2+1.1s-80

Solution for 0=0.08s^2+1.1s-80 equation:

0=0.08s^2+1.1s-80

We move all terms to the left:

0-(0.08s^2+1.1s-80)=0

We add all the numbers together, and all the variables

-(0.08s^2+1.1s-80)=0

We get rid of parentheses

-0.08s^2-1.1s+80=0

a = -0.08; b = -1.1; c = +80;
Δ = b2-4ac
Δ = -1.12-4·(-0.08)·80
Δ = 26.81
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$s_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$s_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$s_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-1.1)-\sqrt{26.81}}{2*-0.08}=\frac{1.1-\sqrt{26.81}}{-0.16}
$
$s_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1.1)+\sqrt{26.81}}{2*-0.08}=\frac{1.1+\sqrt{26.81}}{-0.16}
$