SOLUTION: The fuel efficiency for a certain midsize car is given by E(v) = −0.011v2 + 1.446v + 3.8 where E(v) is the fuel efficiency in miles per gallon for a car traveling v mi

Algebra ->  Linear-equations -> SOLUTION: The fuel efficiency for a certain midsize car is given by E(v) = −0.011v2 + 1.446v + 3.8 where E(v) is the fuel efficiency in miles per gallon for a car traveling v mi      Log On


   

Question 833022: The fuel efficiency for a certain midsize car is given by
E(v) = −0.011v2 + 1.446v + 3.8
where E(v) is the fuel efficiency in miles per gallon for a car traveling v miles per hour.
(a) What speed will yield the maximum fuel efficiency? Round to the nearest mile per hour
MPH?
(b) What is the maximum fuel efficiency for this car? Round to the nearest mile per gallon.
MPH?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Because of the minus sign in the co-efficient of v%5E2,
The function is a parabola with a peak.
The formula for the peak is:
+v%5Bmax%5D+=+-b%2F%282a%29+ where
+a+=+-.011+
+b+=+1.446+
+v%5Bmax%5D+=+-1.446%2F%282%2A%28-.011%29%29+
+v%5Bmax%5D+=+1.446%2F.022+
You can finish this. You have the speed that gives
you +E%28v%29+. Now plug +v%5Bmax%5D+ back into the
equation to get +E%28v%29%5Bmax%5D+