0=111+5.04t-4.9t2

Solution for 0=111+5.04t-4.9t2 equation:

0=111+5.04t-4.9t^2

We move all terms to the left:

0-(111+5.04t-4.9t^2)=0

We add all the numbers together, and all the variables

-(111+5.04t-4.9t^2)=0

We get rid of parentheses

4.9t^2-5.04t-111=0

a = 4.9; b = -5.04; c = -111;
Δ = b2-4ac
Δ = -5.042-4·4.9·(-111)
Δ = 2201.0016
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-5.04)-\sqrt{2201.0016}}{2*4.9}=\frac{5.04-\sqrt{2201.0016}}{9.8}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-5.04)+\sqrt{2201.0016}}{2*4.9}=\frac{5.04+\sqrt{2201.0016}}{9.8}
$