document.write( "Question 83039: A rectangular garden is to be surrounded by a walkway of constant width. The gardens dimensions are 30ft. by 40 ft. The total area,m garden plus walkway, is to be 1800ft^2. What must be the width of the walkway to the nearest thousandth? \n" ); document.write( "
Algebra.Com's Answer #59593 by ankor@dixie-net.com(22740)\"\" \"About 
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A rectangular garden is to be surrounded by a walkway of constant width. The garden's dimensions are 30ft by 40ft. The total area, garden plus walkway, is to be 1800ft^2. What must be the width of the walkway to the nearest thousandth?
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\n" ); document.write( "Let x = width of the walkway
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\n" ); document.write( "Draw this out labeling the walkway width as x, and the inner rectangle
\n" ); document.write( "representing the garden as 30 by 40. It will be apparent that the overall
\n" ); document.write( "dimensions will be (2x+30) by (2x+40), the area of that is given as 1800 sqft
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\n" ); document.write( "(2x + 30) * (2x + 40) = 1800
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\n" ); document.write( "FOIL
\n" ); document.write( "4x^2 + 140x + 1200 = 1800
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\n" ); document.write( "4x^2 + 140x + 1200 - 1800 = 0
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\n" ); document.write( "4x^2 + 140x - 600 = 0
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\n" ); document.write( "Simplify, divide eq by 4 and you have:
\n" ); document.write( "x^2 + 35x - 150 = 0
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\n" ); document.write( "Use the quadratic formula to find x: a=1; b=35; c=-150
\n" ); document.write( "\"x+=+%28-35+%2B-+sqrt%28+35%5E2+-+4+%2A+1+%2A+-150+%29%29%2F%282%2A1%29+\"
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\n" ); document.write( "\"x+=+%28-35+%2B-+sqrt%28+1225+-+%28-600%29%29%29%2F%282%29+\"
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\n" ); document.write( "\"x+=+%28-35+%2B-+sqrt%28+1225+%2B+600%29%29%2F%282%29+\"
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\n" ); document.write( "Do the math and you will get two solutions; -38.86 and +3.86,
\n" ); document.write( "obviously it's x = 3.86
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\n" ); document.write( "3.86 ft is the width of the walkway
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\n" ); document.write( "Check it:
\n" ); document.write( "2x = 2(3.86) = 7.72
\n" ); document.write( "So we have:
\n" ); document.write( "37.72 * 47.72 = 1799.998 ~ 1800 sq ft
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\n" ); document.write( "How about this? Did it make sense to you? Any questions? \n" ); document.write( "
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