document.write( "Question 632043: x+xy+1=16
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Algebra.Com's Answer #398542 by Edwin McCravy(20063)\"\" \"About 
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document.write( "eq. 1     x+xy+1=16 \r\n" );
document.write( "eq. 2        x-y=1,\r\n" );
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document.write( "Solve eq. 2 for x:\r\n" );
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document.write( "eq. 2        x-y=1\r\n" );
document.write( "eq. 3          x=1+y\r\n" );
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document.write( "Substitute 1+y for x in eq. 1:\r\n" );
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document.write( "eq. 1     x+xy+1=16\r\n" );
document.write( "  (1+y)+(1+y)y+1=16\r\n" );
document.write( "      1+y+y+y²+1=16\r\n" );
document.write( "         y²+2y+2=16\r\n" );
document.write( "        y²+2y-14=0\r\n" );
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document.write( "\"y+=+%28-%282%29+%2B-+sqrt%28+%282%29%5E2-4%2A%281%29%2A%28-14%29+%29%29%2F%282%2A%281%29%29+\"\r\n" );
document.write( "\"y+=+%28-2+%2B-+sqrt%284%2B56+%29%29%2F2+\"\r\n" );
document.write( "\"y+=+%28-2+%2B-+sqrt%2860%29%29%2F2+\"\r\n" );
document.write( "\"y+=+%28-2+%2B-+sqrt%284%2A15%29%29%2F2+\"\r\n" );
document.write( "\"y+=+%28-2+%2B-+2sqrt%2815%29%29%2F2+\"\r\n" );
document.write( "\"y+=+%282%28-1+%2B-+sqrt%2815%29%29%29%2F2+\"\r\n" );
document.write( "\"y+=+%28cross%282%29%28-1+%2B-+sqrt%2815%29%29%29%2Fcross%282%29+\"\r\n" );
document.write( "\"y+=+-1+%2B-+sqrt%2815%29%29+\"\r\n" );
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document.write( "Two solutions for y:\r\n" );
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document.write( "\"y+=+-1+%2B+sqrt%2815%29%29+\" and \"y+=+-1+-+sqrt%2815%29%29+\"\r\n" );
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document.write( "Use eq. 3 with first solution for y          \r\n" );
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document.write( "     x=1+y                                \r\n" );
document.write( "     x=1+\"-1+%2B+sqrt%2815%29%29+\"               \r\n" );
document.write( "     x=\"sqrt%2815%29\"                       \r\n" );
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document.write( "First solution:\r\n" );
document.write( "then x+y=\"sqrt%2815%29\"+(\"-1+%2B+sqrt%2815%29%29+\")\r\n" );
document.write( "then x+y=\"-1%2B+2sqrt%2815%29%29+\"\r\n" );
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document.write( "Use eq. 3 with second solution for y          \r\n" );
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document.write( "     x=1+y                                \r\n" );
document.write( "     x=1+\"-1+-+sqrt%2815%29%29+\"               \r\n" );
document.write( "     x=\"-sqrt%2815%29\"                       \r\n" );
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document.write( "Second solution:\r\n" );
document.write( "then x+y=\"-sqrt%2815%29\"+(\"-1+-+sqrt%2815%29%29+\")\r\n" );
document.write( "then x+y=\"-1-+2sqrt%2815%29%29+\"\r\n" );
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document.write( "Edwin
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