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?

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

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? 

 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