document.write( "Question 1170722: The highway mileage min miles per gallon for a compact car is approximated by m(s) = -0.025s^2+2.45s-30 where s is the speed in miles perhour.
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\n" ); document.write( "a.If the car is traveling 65mph, what will the highway mileage be?
\n" ); document.write( "b.If the car is traveling 20mph, what will the highway mileage be?
\n" ); document.write( "c.What speed will the car be traveling if the mileage is 28 miles per gallon?
\n" ); document.write( "d.What speed will the car be traveling if the mileage is 0 miles per gallon?
\n" ); document.write( "e.What is the maximum mileage for this compact car to the nearest tenth of a mile per gallon? What speed results in this mileage? \n" ); document.write( "
Algebra.Com's Answer #795635 by ankor@dixie-net.com(22740)\"\" \"About 
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The highway mileage min miles per gallon for a compact car is approximated by m(s) = -0.025s^2+2.45s-30 where s is the speed in miles per hour.\r
\n" ); document.write( "\n" ); document.write( "a.If the car is traveling 65mph, what will the highway mileage be?
\n" ); document.write( "s = 65, therefore
\n" ); document.write( "m(s) = -0.025(65^2) + 2.45(65) - 30
\n" ); document.write( "m(s) = -.025(4225) + 159.25 - 30
\n" ); document.write( "m(s) = -105.625 + 129.25
\n" ); document.write( "m(s) = 23.625 mpg
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\n" ); document.write( "b.If the car is traveling 20mph, what will the highway mileage be?
\n" ); document.write( "s = 20
\n" ); document.write( "m(s) = -0.025(400)+2.45(20)-30
\n" ); document.write( "m(s) = -10 + 49 - 30
\n" ); document.write( "m(s) = 9 mpg
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\n" ); document.write( "c.What speed will the car be traveling if the mileage is 28 miles per gallon?
\n" ); document.write( "-0.025s^2 + 2.45s - 30 = 28
\n" ); document.write( "-0.025s^2 + 2.45s - 30 - 28 = 0
\n" ); document.write( "-0.025s^2 + 2.45s - 58 = 0
\n" ); document.write( "use the quadratic formula a=-.025, b=2.45, c=-58
\n" ); document.write( "I got a positive solution of:
\n" ); document.write( "s = 40 mph
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\n" ); document.write( "d. What speed will the car be traveling if the mileage is 0 miles per gallon?
\n" ); document.write( "-0.025s^2 + 2.45s - 30 = 0
\n" ); document.write( "using the quadratic formula; a=-.025, b=2.45, c=-30
\n" ); document.write( "Got a rather silly answer of 14.35 mph when mpg = 0
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\n" ); document.write( "e.What is the maximum mileage for this compact car to the nearest tenth of a mile per gallon? What speed results in this mileage?
\n" ); document.write( "That will occur on the axis of symmetry, x=-b/(2a)
\n" ); document.write( "s = \"%28-2.45%29%2F%282%2A-.025%29\"
\n" ); document.write( "s = 49 mph
\n" ); document.write( "Find the mpg
\n" ); document.write( "m(s) = -0.025(49^2) + 2.45(49) - 30
\n" ); document.write( "m(s) =-.025(2401) + 120.05 - 30
\n" ); document.write( "M(s) = -60.025 + 90.05
\n" ); document.write( "m(s) = 30.025 ~ 30 mpg
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\n" ); document.write( "Graphically
\n" ); document.write( "\"+graph%28+300%2C+200%2C+-10%2C+100%2C+-10%2C+50%2C+-.025x%5E2%2B2.45x-30%2C+30%2C+24%29+\"\r
\n" ); document.write( "\n" ); document.write( "vertical y is mpg, horizontal x is mph, green line is mpg=30, blueline is 24 mpg \n" ); document.write( "
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