document.write( "Question 109747: A rectangular lawn is 60 feet by 80 feet. How wide a uniform strip must be cut around the edge when mowing the grass in order that half of the grass be cut? \n" ); document.write( "
Algebra.Com's Answer #79988 by ankor@dixie-net.com(22740)\"\" \"About 
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A rectangular lawn is 60 feet by 80 feet. How wide a uniform strip must be cut around the edge when mowing the grass in order that half of the grass be cut?
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\n" ); document.write( "Let x = width of the mowed area
\n" ); document.write( "then
\n" ); document.write( "Un-mowed area = half the total area
\n" ); document.write( "(60-2x)* (80-2x) = \"1%2F2\"(60*80)
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\n" ); document.write( "4800 - 280x + 4x^2 = 2400
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\n" ); document.write( "Arrange as a quadratic equation:
\n" ); document.write( "4x^2 - 280x + 4800 - 2400 = 0
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\n" ); document.write( "4x^2 - 280x + 2400 = 0
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\n" ); document.write( "Simplify, divide by 4:
\n" ); document.write( "x^2 - 70x + 600 = 0
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\n" ); document.write( "Factor this to:
\n" ); document.write( "(x - 60)(x - 10) = 0
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\n" ); document.write( "x = +10 ft uniform strip is the only solution that makes sense.
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\n" ); document.write( "Check solution
\n" ); document.write( "(60-20) * (80-20) = 2400, half the total area
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\n" ); document.write( "Did this make sense to you? Any questions? \n" ); document.write( "
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