A toy rocket is launched from a 4.24.2 m high platform in such a way that its height, h (in meters), after t seconds is given by the equation h equals negative 4.9 t squared plus 28.7 t plus 4.2h=−4.9t2+28.7t+4.2. how long will it take for the rocket to hit the ground?

[tex]0 = -4.9t^2+28.7t+4.2\\ \\0 = 4.9t^2-28.7t-4.2\\ \\t = \frac{-28.7+\sqrt{(-28.7)^2-4*4.9*(-4.2)} }{2*4.9} =6seconds \\ \\ or\\ \\ t = \frac{-28.7-\sqrt{(-28.7)^2-4*4.9*(-4.2)} }{2*4.9}=-0.143seconds[/tex]

So t = 6 seconds and t = -0.143 seconds( negative time is not possible)

So the toy rocket will take 6 seconds before it reaches ground.

A toy rocket is launched from a 4.24.2 m high platform in such a way that its​ height, h​ (in meters), after t seconds is given by the equation h equals negative 4.9 t squared plus 28.7 t plus 4.2h=−4.9t2+28.7t+4.2. how long will it take for the rocket to hit the​ ground?

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A toy rocket is launched from a 4.24.2 m high platform in such a way that its height, h (in meters), after t seconds is given by the equation h equals negative 4.9 t squared plus 28.7 t plus 4.2h=−4.9t2+28.7t+4.2. how long will it take for the rocket to hit the ground?