A rocket is shot into the air and follows a parabolic path given by h = -4.9t^2 + 58.8t + 8.6 where h is the height of the rocket above the ground in meters and t is the elapsed time in seconds. Determine how long the rocket will be above 150 m.

Answer 1

What is t when h = 150 ?
150 = -4.9 t^2 + 58.8 t + 8.6
or
4.9 t^2 - 58.8 t + 141.4 = 0
solve quadratic
https://www.mathsisfun.com/quadratic-equation-solver.html
8.67 - 3.33 = time above 150