Editorial for DMOPC '14 Contest 7 P1 - Flare

Remember to use this editorial only when stuck, and not to copy-paste code from it. Please be respectful to the problem author and editorialist.
Submitting an official solution before solving the problem yourself is a bannable offence.

Solving the roots for $y = vt + \frac{1}{2}gt^2$ ~y = vt + \frac{1}{2}gt^2~ gives $t = \frac{2v}{g} = \frac{v}{4.9}$ ~t = \frac{2v}{g} = \frac{v}{4.9}~.