A toy rocket was launched from the ground. The function f(x) = -16x2 + 192x shows the height of the rocket f(x), in feet, from the ground at time x seconds.

What is the axis of symmetry of the graph of f(x) and what does it represent?

Question

A toy rocket was launched from the ground. The function f(x) = -16x2 + 192x shows the height of the rocket f(x), in feet, from the ground at time x seconds.

What is the axis of symmetry of the graph of f(x) and what does it represent?

anonymous · Answer

x = 12; it takes 12 seconds to reach the maximum height and 12 seconds to fall back to the ground

 x = 12; it takes 12 seconds to reach the maximum height and 24 seconds to fall back to the ground

 x = 6; it takes 6 seconds to reach the maximum height and 6 seconds to fall back to the ground

 x = 6; it takes 6 seconds to reach the maximum height and 3 seconds to fall back to the ground

phi · Answer

can you find the x-value of the vertex?

anonymous · Answer

Factor the problem: 

f(x) = 16x(x-12)

anonymous · Answer

@DSS I honestly have no idea how to factor that

anonymous · Answer

I pulled out the greatest common factors of -16x2 + 192x

anonymous · Answer

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anonymous · Answer

The rocket reaches the maximum height at 6.
-16 * 6^2 + 192*6 = 576

(6,176) is the maximum height.    It's at 0 after 12 seconds total (12, 0)...it looks like it took 6 seconds to reach maximum and 6 back to 0. Hope  that's right.

anonymous · Answer

@DSS THANK YOU SOOOOOO MUCH!!!!!! I understand it very well too!!!