document.write( "Question 69884: A rectangular garden is to be surrounded by a walkway of constant width. The garden's dimensions are 30ft by 40ft. The total are, garden plus walkway, is to be 1800ft^2. What must be the width of the walkway to the nearest thousandth? \r
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Algebra.Com's Answer #49794 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 1800 ft^2. What must be the width of the walkway to the nearest thousandth?
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\n" ); document.write( "A rough drawing will aid in understanding this:
\n" ); document.write( "Label the garden rectangle as 30 by 40
\n" ); document.write( "Label the width of the walk-way as x,
\n" ); document.write( "It should be apparent, that the outside dimensions, which include the walk-way,
\n" ); document.write( "are (30+2x) by (40+2x):
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\n" ); document.write( "Area of the whole thing is given as 1800 sq ft, so we have:
\n" ); document.write( "(30+2x)*(40+2x) = 1800
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\n" ); document.write( "1200 + 60x + 80x + 4x^2 = 1800; FOILed (30+2x)(40+2x)
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\n" ); document.write( "1200 + 140x + 4x^2 - 1800 = 0;
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\n" ); document.write( "4x^2 + 140x - 600 = 0; our old friend, the quadratic equation
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\n" ); document.write( "Simplify, divide equation by 4 and you have:
\n" ); document.write( "x^2 + 35x - 150 = 0\r
\n" ); document.write( "\n" ); document.write( "Does not easily factor, so use the quadratic formula:
\n" ); document.write( "a = 1; b = 35; c = -150
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\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
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\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+1825+%29%29%2F%282%29+\"
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\n" ); document.write( "We are only interested in the positive solution here
\n" ); document.write( "\"x+=+%28%28-35+%2B+42.72%29%29%2F2\"
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\n" ); document.write( "\"x+=+%287.72%29%2F2\"
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\n" ); document.write( "x = 3.860 ft is the width of the path
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\n" ); document.write( "Check our solution; add 2 * 3.86 to the given dimensions; 30 by 40
\n" ); document.write( "37.72 * 47.72 = 1799.9984 ~ 1800
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\n" ); document.write( "How about this? Did it make sense to you? \n" ); document.write( "
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