Problem

A pomegranate is thrown from ground level straight up into the air at time $t=0$ with velocity 128 feet per second. Its height in feet at $t$ seconds is $f(t)=-16 t^{2}+128 t$. Find the time it hits the ground and the time it reaches its highest point.
Hits the ground when $t=$ (include units)
Reaches highest point when $t=$ (include units)
Maximum height $=$ (include units)

Answer

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Answer

Final Answer: The pomegranate hits the ground when \(t = \boxed{8}\) seconds. It reaches its highest point when \(t = \boxed{4}\) seconds. The maximum height is \(\boxed{256}\) feet.

Steps

Step 1 :The pomegranate hits the ground when its height is zero, i.e., when \(f(t) = 0\). We can solve the equation \(-16t^2 + 128t = 0\) to find the time it hits the ground.

Step 2 :The pomegranate reaches its highest point when its velocity is zero. The velocity is the derivative of the height function, \(f'(t) = -32t + 128\). We can solve the equation \(-32t + 128 = 0\) to find the time it reaches its highest point.

Step 3 :The maximum height is the value of the height function at the time it reaches its highest point, i.e., \(f(t)\) at the solution of \(-32t + 128 = 0\).

Step 4 :Final Answer: The pomegranate hits the ground when \(t = \boxed{8}\) seconds. It reaches its highest point when \(t = \boxed{4}\) seconds. The maximum height is \(\boxed{256}\) feet.

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