Casie M.

asked • 09/20/18

A rock is projected directly upward from ground level, and its height as a function of time is h(t)=-60t^2+90t.

a) make a sketch of h(t)
b) Determine the time at which the rock reaches its maximum height, and find that maximum height in feet.
c) For what is the interval will the rock be more than 120 feet above the ground?
d) After how many seconds will the rock hit the ground?

Arturo O.

Is the equation copied correctly?  If the units of height are feet and time is in seconds, the term with t2 should be -16t2.


Casie M.

No I typed It wrong it should be -16t^2+90t


1 Expert Answer


Arturo O. answered • 09/20/18

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