Answer:
h = 256 feet
Step-by-step explanation:
Given that,
The initial velocity of firework, v = 128 ft/s
The acceleration due to gravity is-16 ft/s².
We need to find the maximum height reached by the firework.
The equation for the firework is :
[tex]h(t) = -16t^2 + 128t[/tex]
To find the vertex's x-coordinate, we can use
[tex]t=\dfrac{-b}{2a}\\\\t=\dfrac{-128}{2\times (-16)}\\\\t=4\ s[/tex]
Put all the values in the expression for h (t).
[tex]h(t) = -16(4)^2 + 128(4)\\\\h(t)=256\ ft[/tex]
So, the maximum height reached by the firework is 256 feet.
