document.write( "Question 1171624: Ana has 40 ft of fencing materials to be used for three sides of a rectangular garden, while a wall serves as her fourth side. What measures of the width will give an area of at least 150square ft?
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Algebra.Com's Answer #796547 by ankor@dixie-net.com(22740)\"\" \"About 
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Ana has 40 ft of fencing materials to be used for three sides of a rectangular garden, while a wall serves as her fourth side.
\n" ); document.write( " What measures of the width will give an area of at least 150 square ft
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\n" ); document.write( "L + 2w = 40
\n" ); document.write( "L = 40 - 2w
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\n" ); document.write( "The area
\n" ); document.write( "L * w = 150
\n" ); document.write( "replace L with (40-2w)
\n" ); document.write( "(40-2w)*w = 150
\n" ); document.write( "40w - 2w^2 = 150
\n" ); document.write( "Arrange as a quadratic equation
\n" ); document.write( "-2w^2 + 40w - 150 = 0
\n" ); document.write( "simplify, divide by -2
\n" ); document.write( "w^2 - 20w + 75 = 0
\n" ); document.write( "factors to:
\n" ); document.write( "(w-5)(w-15) = 0
\n" ); document.write( "Two solutions
\n" ); document.write( "w = 5 ft, then L = 30 ft
\n" ); document.write( "and
\n" ); document.write( "w = 15 ft, then L = 10 ft
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