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A ball is thrown into the air with an upward velocity of 100 ft/s. Its height after t seconds is given by the function f(x) = -16t^2 + 64t + 960. What is the maximum height of the ball?

A. 960 feet
B. 1152 feet
C. 1008 feet
D. 1024 feet

2 Answers

6 votes

Answer:

Its D

Explanation:

I used a graphing calculator and I substituted my zeros

Hope this helps :)

User Uniknow
by
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1 vote

Answer:

D. 1024 feet

Explanation:

The height function can be written in vertex form as ...

f(t) = -16(t -2)^2 +1024

This has a maximum value of 1024 (feet) at t=2 (seconds).

The maximum height of the ball is 1024 feet.

_____

Rearranging to vertex form can be accomplished in a few steps:

-16(t^2 -4t) +960 . . . . . factor the leading coefficient from the variable terms

-16(t^2 -4t +4) +960 -(-16)(4) . . . . . add and subtract the square of half the linear term coefficient: (4/2)^2 = 4

-16(t -2)^2 +1024 . . . . . collect terms and put into vertex form

A ball is thrown into the air with an upward velocity of 100 ft/s. Its height after-example-1
User Mike DeAngelo
by
3.9k points