document.write( "Question 1051119: Let x and y be real numbers whose absolute values
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Algebra.Com's Answer #666726 by Edwin McCravy(20067)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Add the two equations:\r\n" );
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document.write( "\"x%5E3%2By%5E3\"\"%22%22=%22%22\"\"27x%2B27y\"\r\n" );
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document.write( "Factor both sides:\r\n" );
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document.write( "\"%28x%2By%29%28x%5E2-xy%2By%5E2%29\"\"%22%22=%22%22\"\"27%28x%2By%29\"\r\n" );
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document.write( "x and y do not have the same absolute values,\r\n" );
document.write( "therefore (x+y) does not equal 0 and we may divide\r\n" );
document.write( "both sides by it.\r\n" );
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document.write( "\"x%5E2-xy%2By%5E2=27\"\r\n" );
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document.write( "------------------------------------------\r\n" );
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document.write( "\"system%28x%5E3+=+20x+%2B+7y+%2C+y%5E3+=+7x+%2B+20y%29\"\r\n" );
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document.write( "Subtract the two equations:\r\n" );
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document.write( "\"x%5E3-y%5E3\"\"%22%22=%22%22\"\"13x-13y\"\r\n" );
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document.write( "Factor both sides:\r\n" );
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document.write( "\"%28x-y%29%28x%5E2%2Bxy%2By%5E2%29\"\"%22%22=%22%22\"\"13%28x-y%29\"\r\n" );
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document.write( "x and y do not have the same absolute values,\r\n" );
document.write( "therefore (x-y) does not equal 0 and we may divide\r\n" );
document.write( "both sides by it.\r\n" );
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document.write( "\"x%5E2%2Bxy%2By%5E2\"\"%22%22=%22%22\"\"13\"\r\n" );
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document.write( "--------------------------\r\n" );
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document.write( "Now we have the two equations:\r\n" );
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document.write( "\"x%5E2%2Bxy%2By%5E2\"\"%22%22=%22%22\"\"13\"\r\n" );
document.write( "\"x%5E2-xy%2By%5E2\"\"%22%22=%22%22\"\"27\"\r\n" );
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document.write( "Subtract them and get\r\n" );
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document.write( "      \"2xy\"\"%22%22=%22%22\"\"-14\"\r\n" );
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document.write( "      \"xy+=+-7\"\r\n" );
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document.write( "Answer: -7\r\n" );
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document.write( "Edwin
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