document.write( "Question 838704: A gardener has a 30 foot by 20 foot rectangular plot of ground. She wants to build a
\n" ); document.write( "brick walkway of uniform width on the border of the plot. If the gardener wants to
\n" ); document.write( "have 400 square feet of ground left for planting, how wide (to 2 decimal places)
\n" ); document.write( "should she build the walkway? \n" ); document.write( "
Algebra.Com's Answer #505237 by stanbon(75887)\"\" \"About 
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A gardener has a 30 foot by 20 foot rectangular plot of ground. She wants to build a
\n" ); document.write( "brick walkway of uniform width on the border of the plot. If the gardener wants to
\n" ); document.write( "have 400 square feet of ground left for planting, how wide (to 2 decimal places)
\n" ); document.write( "should she build the walkway?
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\n" ); document.write( "Draw the picture.
\n" ); document.write( "You have a rectangle inside a rectangle.
\n" ); document.write( "The outer rectangle is 30 by 20
\n" ); document.write( "The inner rectangle is (30-2x) by (20-2x)
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\n" ); document.write( "Area of the inner rectangle is 2(15-x)*2(10-x) = 400
\n" ); document.write( "(15-x)(10-x) = 100
\n" ); document.write( "150-25x + x^2 = 100
\n" ); document.write( "x^2 - 25x + 50 = 0
\n" ); document.write( "x = 2.1922 ft (width of the walkway)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.\r
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