document.write( "Question 628205: A rectangular garden is 60 ft by 80 ft. Part of the garden is torn up to install a sidewalk of uniform width around the garden. The new area of the garden is one sixth of the old area. How wide is the sidewalk?\r
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Algebra.Com's Answer #395469 by ankor@dixie-net.com(22740)\"\" \"About 
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A rectangular garden is 60 ft by 80 ft.
\n" ); document.write( " Part of the garden is torn up to install a sidewalk of uniform width around the garden.
\n" ); document.write( " The new area of the garden is one sixth of the old area.
\n" ); document.write( " How wide is the sidewalk?
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\n" ); document.write( "Let x = the width of the walk
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\n" ); document.write( "The new dimensions of the garden will be (60-2x) by (80-2x)
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\n" ); document.write( "Find the original area: 60*80 = 4800 sq/ft
\n" ); document.write( "Find the new area: \"1%2F6\"*4800 = 800 sq/ft
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\n" ); document.write( "(60-2x)*(80-2x) = 800
\n" ); document.write( "FOIL
\n" ); document.write( "4800 - 120x - 160x + 4x^2 = 800
\n" ); document.write( "Combine on the left as a quadratic equation
\n" ); document.write( "4x^2 - 280x + 4800 - 800 = 0
\n" ); document.write( "4x^2 - 280x + 4000 = 0
\n" ); document.write( "simplify divide by 4
\n" ); document.write( "x^2 - 70x + 1000 = 0
\n" ); document.write( "Factors to
\n" ); document.write( "(x-20)(x-50) = 0
\n" ); document.write( "Two solutions
\n" ); document.write( "x = 50, not reasonable
\n" ); document.write( "and
\n" ); document.write( "x = 20 ft is the width of the walk
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\n" ); document.write( "Check this with the new dimensions (2x = 40):
\n" ); document.write( " (80-40)*(60-40) = 800 sq/ft
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