SOLUTION: A ball is thrown vertically upward. After t seconds, its height h (in feet) is given by the function h(t)= 56t-16tē . What is the maximum height that the ball will reach? Do n

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Question 359046: A ball is thrown vertically upward. After t seconds, its height h (in feet) is given by the function h(t)= 56t-16tē . What is the maximum height that the ball will reach?
Do not round your answer.
*here was my approach
i factored the equation getting:
= 4t(-4t+14)
= 4t = 0 -4t+14 = 0
t = 0 -4t = -14
t = 7/2
The answer i came up with was 3.5ft, is this correct?

Answer by Fombitz(32388)   (Show Source): You can put this solution on YOUR website!
No, that's not correct.
You're solving for when .


when
and
and
and
Using a symmetry argument, then the maximum height must occur when time is between these two values,
Find


ft
.
.
.
You could also have converted the height equation to vertex form, since the maximum value occurs at the vertex.
I use instead of here because (,) is traditionally the vertex.
Complete the square.




So then the maximum value of occurs at
.
.
.
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