document.write( "Question 325299: The length of a rectangle is four more than the width. If the area of the rectangle is 621 m2, find the width and length of the rectangle.
\n" ); document.write( "Let w be the width. Therefore w + 4 is the length.
\n" ); document.write( "w(w +4) = 621
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Algebra.Com's Answer #232955 by jim_thompson5910(35256)\"\" \"About 
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\"w%28w+%2B4%29+=+621\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"w%5E2%2B4w+=+621\" Distribute.\r
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\n" ); document.write( "\n" ); document.write( "\"w%5E2%2B4w+-+621=0\" Subtract 621 from both sides.\r
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\n" ); document.write( "\n" ); document.write( "Notice that the quadratic \"w%5E2%2B4w-621\" is in the form of \"Aw%5E2%2BBw%2BC\" where \"A=1\", \"B=4\", and \"C=-621\"\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for \"w\":\r
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\n" ); document.write( "\n" ); document.write( "\"w+=+%28-B+%2B-+sqrt%28+B%5E2-4AC+%29%29%2F%282A%29\" Start with the quadratic formula\r
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\n" ); document.write( "\n" ); document.write( "\"w+=+%28-%284%29+%2B-+sqrt%28+%284%29%5E2-4%281%29%28-621%29+%29%29%2F%282%281%29%29\" Plug in \"A=1\", \"B=4\", and \"C=-621\"\r
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\n" ); document.write( "\n" ); document.write( "\"w+=+%28-4+%2B-+sqrt%28+16-4%281%29%28-621%29+%29%29%2F%282%281%29%29\" Square \"4\" to get \"16\". \r
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\n" ); document.write( "\n" ); document.write( "\"w+=+%28-4+%2B-+sqrt%28+16--2484+%29%29%2F%282%281%29%29\" Multiply \"4%281%29%28-621%29\" to get \"-2484\"\r
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\n" ); document.write( "\n" ); document.write( "\"w+=+%28-4+%2B-+sqrt%28+16%2B2484+%29%29%2F%282%281%29%29\" Rewrite \"sqrt%2816--2484%29\" as \"sqrt%2816%2B2484%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"w+=+%28-4+%2B-+sqrt%28+2500+%29%29%2F%282%281%29%29\" Add \"16\" to \"2484\" to get \"2500\"\r
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\n" ); document.write( "\n" ); document.write( "\"w+=+%28-4+%2B-+sqrt%28+2500+%29%29%2F%282%29\" Multiply \"2\" and \"1\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"w+=+%28-4+%2B-+50%29%2F%282%29\" Take the square root of \"2500\" to get \"50\". \r
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\n" ); document.write( "\n" ); document.write( "\"w+=+%28-4+%2B+50%29%2F%282%29\" or \"w+=+%28-4+-+50%29%2F%282%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"w+=+%2846%29%2F%282%29\" or \"w+=++%28-54%29%2F%282%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"w+=+23\" or \"w+=+-27\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"w+=+23\" or \"w+=+-27\" \r
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\n" ); document.write( "\n" ); document.write( "Ignore the negative solution (since a negative width doesn't make sense) to find that the width is \"w=23\" meters.
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