You can
put this solution on YOUR website!Your problem statement seems to have some anomalies in it!
The standard formula for the height (as a function of time) of an object propelled upwards from an initial height of

with an initial velocity of

is given by:

where g (the constant of acceleration due to gravity) is 32 ft/sec^2, so your formula should look like:

Your formula also shows two different varaibles. t and x.
So, back to the problem but starting with the correct formul, (the d in your problem will work just as well as the h(t)) we have:

First, we'll find the time, t, at which the height, d, is at its maximum. The graph of the quadradtic equation that we have here is a parabola that opens downward (signified by the negative first term) so its maximum will occur at the vertex of the parabola, and this is given by:

where a = -16 and b = 64, so...

}

secs.
To find the maximum height, we substitute the time, t=2secs into the original equation and solve for d.

feet.
The rock will reach a maximum height of 192 feet.