SOLUTION: Hi there, I could use your help with the following problem:
The fuel efficiency F for a particular car is given by:
F(x) = –.016x^2 + 1.44x + 5.4
where x is the speed of
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-> SOLUTION: Hi there, I could use your help with the following problem:
The fuel efficiency F for a particular car is given by:
F(x) = –.016x^2 + 1.44x + 5.4
where x is the speed of
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Question 1040585: Hi there, I could use your help with the following problem:
The fuel efficiency F for a particular car is given by:
F(x) = –.016x^2 + 1.44x + 5.4
where x is the speed of the car in miles per hour (mph) and F(x) is the corresponding fuel efficiency in miles per gallon (mpg).
What is the fuel efficiency if the car’s speed is 20 mph?
I came up with 34.3024, but I"m confused on the next question:
What speed will yield the maximum fuel efficiency?
any help or guidance would be greatly appreciated! Thank yoU! Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website!
(a)
What is the fuel efficiency if the car’s speed is 20 mph? mi/gal
Check my math on this!
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This is a parabola, so it has either a single maximum or
a single minimum.
The minus sign in front of the term tells me
this is a maximum
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The formula for the x-value of the vertex ( peak ) is: when the form of the equation is:
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This says the peak mi/gal occurs when the speed is 45 mi/hr
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Plug this value of back into the equation
The maximum fuel efficiency is 37.8 mi/gal
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Here's the plot:
