Question

A small toy rocket is launched from a 32-foot pad. The height ( h, in feet) of the rocket t seconds after taking off is given by the formula h=−2t2+0t+32 . How long will it take the rocket to hit the ground?t=______(Separate answers by a comma. Write answers as integers or reduced fractions.)

Answer 1

Given: A small toy rocket is launched from a 32-foot pad. The height (h, in feet) of the rocket t seconds after taking off is given by the formula

`h=-2t^2+0t+32`

Required: To find out how long will it take the rocket to hit the ground.

Explanation: When the rocket touches the ground its height will be zero i.e.,

`\begin{gathered} -2t^2+0t+32=0 \\ 2t^2=32 \\ t^2=16 \end{gathered}`

Which gives

`t=\pm4`

Neglecting the negative value of t since time cannot be negative. We have

`t=4\text{ seconds}`

Final Answer: Time, t=4 seconds.