document.write( "Question 1106170: solve
\n" ); document.write( "2x-y=21
\n" ); document.write( " x=4y
\n" ); document.write( "

Algebra.Com's Answer #721110 by Alan3354(69443)\"\" \"About 
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solve
\n" ); document.write( "2x-y=21
\n" ); document.write( " x=4y
\n" ); document.write( "===============
\n" ); document.write( "You should say \"solve for x & y\"
\n" ); document.write( "-----
\n" ); document.write( "Sub for x in the 1st equation.
\n" ); document.write( "2x-y=21
\n" ); document.write( "2*4y - y = 21
\n" ); document.write( "8y - y = 21
\n" ); document.write( "7y = 21
\n" ); document.write( "y = 3
\n" ); document.write( "============
\n" ); document.write( "x = 4y
\n" ); document.write( "x = 12
\n" ); document.write( "
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