document.write( "Question 1189792: A square garden has a walkway 3 ft wide around its outer edge.If the area of the entire garden, including the walkway, is 18,000 ft^2, what are the
\n" ); document.write( "dimensions of the planted area?
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Algebra.Com's Answer #821258 by math_tutor2020(3817)\"\" \"About 
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\n" ); document.write( "x = side length of the planted area (ie we ignore the walkway)\r
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\n" ); document.write( "\n" ); document.write( "When considering the walkway, we add on 3+3 = 6 feet for each dimension of the square.
\n" ); document.write( "The x by x square bumps up to (x+6) by (x+6)\r
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\n" ); document.write( "\n" ); document.write( "The larger square has area of
\n" ); document.write( "(x+6)^2
\n" ); document.write( "(x+6)*(x+6)
\n" ); document.write( "x(x+6)+6(x+6)
\n" ); document.write( "x^2+6x+6x+36
\n" ); document.write( "x^2+12x+36\r
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\n" ); document.write( "\n" ); document.write( "Set this area expression equal to the desired area (18,000) and solve for x.
\n" ); document.write( "x^2+12x+36 = 18,000
\n" ); document.write( "x^2+12x+36-18,000 = 0
\n" ); document.write( "x^2+12x-17,964 = 0\r
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\n" ); document.write( "\n" ); document.write( "Now turn to the quadratic formula
\n" ); document.write( "\"x+=+%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-%2812%29%2B-sqrt%28%2812%29%5E2-4%281%29%28-17964%29%29%29%2F%282%281%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-12%2B-sqrt%2872000%29%29%2F%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-12%2B-268.3281573%29%2F%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-12%2B268.3281573%29%2F%282%29\" or \"x+=+%28-12-268.3281573%29%2F%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28256.3281573%29%2F%282%29\" or \"x+=+%28-280.32815728%29%2F%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+128.16407865\" or \"x+=+-140.16407863\"\r
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\n" ); document.write( "\n" ); document.write( "We ignore the negative x value because we cannot have negative side lengths.\r
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\n" ); document.write( "\n" ); document.write( "The square planted area is roughly 128.16 feet by 128.16 feet.\r
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\n" ); document.write( "\n" ); document.write( "Here's another way to solve.\r
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\n" ); document.write( "\n" ); document.write( "We start off with some smaller square representing the plants only. Adding on the walkway of uniform with around all the edges will get us some larger square.\r
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\n" ); document.write( "\n" ); document.write( "Let's say this larger square has side lengths of W. So W^2 is the area of this larger square.
\n" ); document.write( "Set it equal to the 18,000 figure and solve for W\r
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\n" ); document.write( "\n" ); document.write( "\"W%5E2+=+18000\"\r
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\n" ); document.write( "\n" ); document.write( "\"W+=+sqrt%2818000%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"W+=+134.164079\"\r
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\n" ); document.write( "\n" ); document.write( "The side lengths of the larger square are roughly 134.164079 feet\r
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\n" ); document.write( "\n" ); document.write( "We then subtract off 6 feet due to the 3+3 = 6 figure calculated earlier
\n" ); document.write( "134.164079 - 6 = 128.164079\r
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\n" ); document.write( "\n" ); document.write( "We get the same result of 128.16 as earlier.\r
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\n" ); document.write( "\n" ); document.write( "Depending on your preferences, this option may be much easier compared to the last method.
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