I don't understand why you titled this thread "polynomial inequalities." From the data you have been given you have . So the formula becomes:
Rearrange and solve for t.
The function s(t)= -1/2gt^{2 }+v_{0}t +S_{o} can be used to calculate s, the height above a planet's surface in meters, where g is the acceleration due to gravity t is the time in seconds,V_{o} is the initial velocity in meters per second and s_{o} is the initial height in meters. The acceleration due to gravity on mars is g=-3.92 m/s^{2}. Find to two decimal places how long it takes an object to hit the surface of mars if the object is dropped from 1000m above the surface.