An object is 19.6 meters per second (m/s) from a platform, the equation of the object’s height h at time t seconds after launch is h(t)=-4.9t2+19.6t+58.8, where h is in meters (assume nothing else, such as wind, affects the object’s path).
"An object is < insert some unit of distance> from a platform",
you have inserted a velocity, thus this makes no sense.
Furthermore, you forgot to ask a question.