Question 209950

{{{4.9t^2 + v[0]t= s}}} where S = the distance above ground (the height or altitude), t = time in seconds, and {{{v[0]}}} is the initial velocity (zero in this case).
{{{4.9t^2 = 2265}}} Divide both sides by 4.9
{{{t^2 = 462.24489}}} Now take the square root of both sides.
{{{highlight(t = 21.5)}}}seconds. (Rounded to the nearest tenth)