SOLUTION: The amount of background noise is important to tv news reporters. One station developed the formula N=-t squared +12t+54 showing the noise level in decibels(N) as it relates to the

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Question 204808: The amount of background noise is important to tv news reporters. One station developed the formula N=-t squared +12t+54 showing the noise level in decibels(N) as it relates to the time after the speaker stops talking in seconds(t).How many seconds after the speaker stops will the noise level be the greatest? Write and tell how decided.
I would appreciate your help on this word problem.
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
this is a quadratic function with a maximum value (coefficient of the squared term is NEGATIVE)

the maximum lies on the axis of symmetry ___ the general equation for the axis is x = -b / 2a

in this case ___ t = -12 / (2 * -1) = 6

N max occurs at t = 6 sec