A small rocket is launched from a height of 6 feet off of the ground at an initial upward velocity of 64 feet per second. Its height is given by the equation 2003-18-06-00-00_files/i0020000.jpg, where h is the height of the rocket in feet and t is the time since liftoff in seconds. At what time is the rocket 54 feet in the air?

Question

Mercury · Answer

h = -16t^2 + 64t + 6

since it wants the time at which the rocket is 54 feet in the air, let h = 54 and solve for t.

there's a couple of ways you could go from there (quadratic formula, completing the square, etc.)