A hot-air balloon is rising upward with a constant speed of 2.53 m/s. When the balloon is 5.82 m above the ground, the balloonist accidentally drops a compass over the side of the balloon. How much time elapses before the compass hits the ground?

Answer 1

Vi = 2.53
Hi = 5.82

0 = Hi + Vi t - 4.9 t^2

4.9 t^2 - 2.53 t - 5.82 = 0
solve quadratic for t
eg : http://www.mathportal.org/calculators/polynomials-solvers/polynomial-roots-calculator.php