document.write( "Question 1209394: Let x and y be complex numbers. If x + y = 2 and xy = 7 - x^2 - y^2, then what is x^2 + y^2? \n" ); document.write( "
Algebra.Com's Answer #848748 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "As the last tutor showed, \r\n" );
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document.write( "{x,y} = {3,-1} and x2 + y2 = 9 + 1 = 10\r\n" );
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document.write( "What the student should observe here is that \r\n" );
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document.write( "All REAL numbers ARE COMPLEX numbers!\r\n" );
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document.write( "3 and -1 are complex numbers because they are 3 + 0i and -1 + 0i respectively.\r\n" );
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document.write( "Nobody said the coefficient of \" i \" cannot be 0. And if it's 0, the number\r\n" );
document.write( "is still complex.  It's both REAL and COMPLEX.\r\n" );
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document.write( "Edwin

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