document.write( "Question 1166190: A farmer has a 200 feet by 40 feet rectangular field that he wants to increase by 24.8% by cultivating a strip of uniform width around the current field. How wide of a strip should he cultivate around the edge of his field to do this? \n" ); document.write( "
Algebra.Com's Answer #790727 by ankor@dixie-net.com(22740)\"\" \"About 
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A farmer has a 200 feet by 40 feet rectangular field that he wants to increase by 24.8% by cultivating a strip of uniform width around the current field.
\n" ); document.write( " How wide of a strip should he cultivate around the edge of his field to do this?
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\n" ); document.write( "Find the area of the original field: 200 * 40 = 8000 sq/ft
\n" ); document.write( "Find the area of the new field: 1.248 * 8000 = 9984 sq/ft
\n" ); document.write( ":
\n" ); document.write( "let x = the width of the strip around the original field
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\n" ); document.write( "(2x+200)*(2x+40) = 9984
\n" ); document.write( "FOIL
\n" ); document.write( "4x^2 + 80x + 400x + 8000 = 9984
\n" ); document.write( "Arrange as a quadratic equation
\n" ); document.write( "4x^2 + 480x + 8000 - 9984 = 0
\n" ); document.write( "4x^2 + 480x - 1984 = 0
\n" ); document.write( "simplify, divide by 4
\n" ); document.write( "x^2 + 120x - 496 = 0
\n" ); document.write( "Use the quadratic formula a=1; b=120, c=-496, but this will factor to
\n" ); document.write( "(x-4)(x+124) = 0
\n" ); document.write( "positive solution is what we want here
\n" ); document.write( "x = 4 ft is the width of the strip around the field
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\n" ); document.write( ":
\n" ); document.write( "See if that works
\n" ); document.write( "208 * 48 = 9984 \n" ); document.write( "
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