Question

A flare was launched straight up from the ground with an initial velocity of 176 ft/s and returned to the ground after 11 s. The height of the flare t seconds after launch is modeled by the function f(t)=−16t2+176t . What is the maximum height of the flare, in feet?

Answer 1

the answer is 484 just took the test 

Answer 2

484 feet is the answer.

Explanation:

Maximum value of f(t) =
`-16t^(2)+176t \\`

is given by when t =
`(-176)/(2(-16))  \\`

which give t = 5.5 seconds

maximum height is when we plug t = 5.5 seconds in equation

more over time of flight is 11 seconds (given )

it will be at its maximum when time is half of 11 seconds.

that is 5.5 seconds

maximum height is obtained by plugging t = 5.5seconds.

f(5.5) = -16(5.5)(5.5) + 176(5.5)

= -484 +968

= 484 feet