document.write( "Question 99587: Construction. A garden area is 30ft long and 20 ft wide. A path of uniform width is set around the edge. If the remaining garden area is 400ft^2, what is teh width of the path? \n" ); document.write( "
Algebra.Com's Answer #72452 by ankor@dixie-net.com(22740)\"\" \"About 
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A garden area is 30 ft long and 20 ft wide. A path of uniform width is set around the edge. If the remaining garden area is 400 ft^2, what is the width of the path?
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\n" ); document.write( "Draw diagram of this; label the outside dimensions of the rectangle 30 by 20.
\n" ); document.write( "Label the width of the path as x, it will be apparent that the dimensions of
\n" ); document.write( "the garden (inside the path), will be (30-2x) by (20-2x)
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\n" ); document.write( "The area of the garden is given as 400 sq/ft
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\n" ); document.write( "A simple area equation:
\n" ); document.write( ":
\n" ); document.write( "length times width = 400 sq/ft
\n" ); document.write( "(30-2x) * (20-2x) = 400
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\n" ); document.write( "FOIL:
\n" ); document.write( "600 - 60x - 40x + 4x^2 = 400
\n" ); document.write( "4x^2 - 100x + 600 = 400
\n" ); document.write( "4x^2 - 100x + 600 - 400 = 0
\n" ); document.write( "4x^2 - 100x + 200 = 0; a quadratic equation
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\n" ); document.write( "Simplify, divide by 4 and you have:
\n" ); document.write( "x^2 - 25x + 50 = 0
\n" ); document.write( ":
\n" ); document.write( "We need to use the quadratic formula to solve this: a=1; b=-25;; c=50
\n" ); document.write( "\"x+=+%28-%28-25%29+%2B-+sqrt%28+-25%5E2-4%2A1%2A50+%29%29%2F%282%2A1%29+\"
\n" ); document.write( ":
\n" ); document.write( "\"x+=+%28%2B25+%2B-+sqrt%28625+-+200+%29%29%2F%282%29+\"
\n" ); document.write( ":
\n" ); document.write( "\"x+=+%2825+%2B-+sqrt%28425+%29%29%2F%282%29+\"
\n" ); document.write( ":
\n" ); document.write( "Two solutions:
\n" ); document.write( "\"x+=+%2825+%2B+20.62%29%2F%282%29+\"
\n" ); document.write( "\"x+=+45.62%2F2\"
\n" ); document.write( "x = 22.8, not a possible solution, obviously
\n" ); document.write( "and
\n" ); document.write( "\"x+=+%2825+-+20.62%29%2F%282%29+\"
\n" ); document.write( "\"x+=+4.38%2F2\"
\n" ); document.write( "x = 2.19 ft is the width of the path
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\n" ); document.write( "Check our solution by finding the area of the garden
\n" ); document.write( "We have to subtract 2x from the outside dimensions: 2*2.19 = 4.38
\n" ); document.write( ":
\n" ); document.write( "(30-4.38) * (20-4.38) =
\n" ); document.write( " 25.62 * 15.62 = 400.2 ~ 400 sq/ft
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