document.write( "Question 890599: `If x–y=7 and xy=6 then find the value of x^4+1/x^4 \n" ); document.write( "

Algebra.Com's Answer #539167 by JulietG(1812) $\"\"$ $\"About$

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If xy = 6, what are the possibilities?
\n" ); document.write( "x=6, y=1
\n" ); document.write( "x=3, y=2
\n" ); document.write( "x=2, y=3
\n" ); document.write( "x=1, y=6
\n" ); document.write( "and the negatives of the above pairs.
\n" ); document.write( "None of those pairs fits the equation x-y=7
\n" ); document.write( "Is it perhaps supposed to be x+y=7? In that case, xy can either be 6,1 or 1,6.
\n" ); document.write( "Using 6,1...
\n" ); document.write( " $\"6%5E4\"$ + $\"1%2F6%5E4\"$ = 1296
\n" ); document.write( "Using 1,6...
\n" ); document.write( " $\"1%5E4\"$ + $\"1%2F1%5E4\"$ = 2
\n" ); document.write( ".
\n" ); document.write( "Please repost if the assumptions are incorrect. \n" ); document.write( "

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