document.write( "Question 151681: Can anyone seem to help me with this problem? I have come to a complete blank on it.\r
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\n" ); document.write( "\n" ); document.write( "Question 64\r
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\n" ); document.write( "The perimeter of the cover of an address book is 14 inches, and the diagonal measures 5 inches. What are the length and width of the cover?
\n" ); document.write( "x^2 + x^2 = 5^2
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\n" ); document.write( "x^4 - 25 = 14\r
\n" ); document.write( "\n" ); document.write( "I do not know what to do next. I followed the Pythagorean steps, but cannot figure out what has gone wrong.
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\n" ); document.write( "\n" ); document.write( "Amanda
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Algebra.Com's Answer #111503 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Let x=width and y=length\r
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\n" ); document.write( "\n" ); document.write( "Remember, the perimeter of any rectangle is:\r
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\n" ); document.write( "\n" ); document.write( "\"P=2x%2B2y\"\r
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\n" ); document.write( "\n" ); document.write( "\"14=2x%2B2y\" Plug in \"P=14\" (the given perimeter)\r
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\n" ); document.write( "\n" ); document.write( "\"14-2x=2y\" Subtract \"2x\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"2y=-2x%2B14\" Rearrange the terms\r
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\n" ); document.write( "\n" ); document.write( "\"y=-x%2B7\" Divide both sides by 2 to isolate y\r
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\n" ); document.write( "\n" ); document.write( "Through the use of pythagoreans theorem, we get:\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2By%5E2=5%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2By%5E2=25\" Square 5 to get 25\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B%28-x%2B7%29%5E2=25\" Plug in \"y=-x%2B7\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2Bx%5E2-14x%2B49=25\" FOIL\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2Bx%5E2-14x%2B49-25=0\" Subtract 25 from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"2x%5E2-14x%2B24=0\" Combine like terms. Note: \"x%5E2%2Bx%5E2%3C%3Ex%5E4\"\r
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\n" ); document.write( "\n" ); document.write( "Notice we have a quadratic equation in the form of \"ax%5E2%2Bbx%2Bc\" where \"a=2\", \"b=-14\", and \"c=24\"\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for x\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%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( "\"x+=+%28-%28-14%29+%2B-+sqrt%28+%28-14%29%5E2-4%282%29%2824%29+%29%29%2F%282%282%29%29\" Plug in \"a=2\", \"b=-14\", and \"c=24\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2814+%2B-+sqrt%28+%28-14%29%5E2-4%282%29%2824%29+%29%29%2F%282%282%29%29\" Negate \"-14\" to get \"14\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2814+%2B-+sqrt%28+196-4%282%29%2824%29+%29%29%2F%282%282%29%29\" Square \"-14\" to get \"196\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2814+%2B-+sqrt%28+196-192+%29%29%2F%282%282%29%29\" Multiply \"4%282%29%2824%29\" to get \"192\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2814+%2B-+sqrt%28+4+%29%29%2F%282%282%29%29\" Subtract \"192\" from \"196\" to get \"4\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2814+%2B-+sqrt%28+4+%29%29%2F%284%29\" Multiply \"2\" and \"2\" to get \"4\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2814+%2B-+2%29%2F%284%29\" Take the square root of \"4\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2814+%2B+2%29%2F%284%29\" or \"x+=+%2814+-+2%29%2F%284%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2816%29%2F%284%29\" or \"x+=++%2812%29%2F%284%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+4\" or \"x+=+3\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So the widths are \"x+=+4\" or \"x+=+3\" \r
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\n" ); document.write( "\"y=-x%2B7\" Go back to the second equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=-4%2B7\" Plug in \"x+=+4\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=3\" Add\r
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\n" ); document.write( "\n" ); document.write( "So if the width is 4 inches, the length is 3 inches\r
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\n" ); document.write( "\"y=-x%2B7\" Go back to the second equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=-3%2B7\" Plug in \"x+=+3\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=4\" Add\r
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\n" ); document.write( "\n" ); document.write( "So if the width is 3 inches, the length is 4 inches\r
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\n" ); document.write( "\n" ); document.write( "Note: the length is usually the longer of the two. So your book probably has the width of 3 inches and a length of 4 inches\r
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