Answer:
69 feet
Step-by-step explanation:
we have
where
h(t) is the height of the ball
t is the time in seconds
we know that the given equation is a vertical parabola open downward
The vertex is the maximum
so
the y-coordinate of the vertex represent the maximum height of the ball
Convert the quadratic equation into vertex form
The equation in vertex form is equal to
where
(h,k) is the vertex of the parabola
the vertex is the point (2,69)
therefore
The maximum height is 69 ft
Answer:
Step-by-step explanation:
The usual equation used for the vertical component of ballistic motion is ...
h(t) = -16t² +v₀t +h₀
where v₀ is the initial upward velocity, and h₀ is the initial height. Units of distance are feet, and units of time are seconds.
Your problem statement gives ...
v₀ = 64 ft/s
h₀ = 8 ft
so the equation of height is ...
h(t) = -16t² +64t +8
__
For quadratic ax² +bx +c, the axis of symmetry is x=-b/(2a). Then the axis of symmetry of the height equation is ...
t = -64/(2(-16)) = 2
The object will reach its maximum height after 2 seconds.
The height at that time will be ...
h(2) = -16(2²) +64(2) +8 = 72
The maximum height will be 72 feet.
