Question 1103806
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It to omit all the literature, or, better to say, if translate this literature to Math or Physics, it means the following:



    How long it will take for freely falling body to hit the ground from the height of 1430 meters.



Using the equation h(t) = -4.9*t^2 + 0*t + 1430  (where "0" means the zero initial velocity, or motionless condition at the highest point 
of the trajectory),

getting ground level means h(t) = 0,  so you need to solve this quadratic equation


-4.9*t^2 + 0*t + 1430 = 0,   or


4.9*t^2 = 1430  ====>  t^2 = {{{1430/4.9}}} = 291.9  ====>  t = {{{sqrt(291.9)}}} = 17.1 seconds (approximately).


<U>Answer</U>.  17.1 seconds (approximately).
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