document.write( "Question 232888: 9x+3y= -39
\n" ); document.write( " -9x+y = 71\r
\n" ); document.write( "\n" ); document.write( "y= 71+9x\r
\n" ); document.write( "\n" ); document.write( "9x+3(71+9x)= -39\r
\n" ); document.write( "\n" ); document.write( "9x+213+27x = -39\r
\n" ); document.write( "\n" ); document.write( "x= ?\r
\n" ); document.write( "\n" ); document.write( "I know that the coefficient of x is 18 but then I forget how to solve for x\r
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Algebra.Com's Answer #171992 by Alan3354(69443)\"\" \"About 
You can put this solution on YOUR website!
9x+3y= -39
\n" ); document.write( "-9x+y = 71
\n" ); document.write( "y= 71+9x
\n" ); document.write( "9x+3(71+9x)= -39
\n" ); document.write( "9x+213+27x = -39
\n" ); document.write( "----------------
\n" ); document.write( "36x + 213 = -39
\n" ); document.write( "36x = -252
\n" ); document.write( "x = -7
\n" ); document.write( "-------
\n" ); document.write( "y = 71+9x = 71 - 63
\n" ); document.write( "y = 8
\n" ); document.write( "---------
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\n" ); document.write( "Elimination would have been easier for this one, since the coefficients of x are the same.
\n" ); document.write( " 9x+3y= -39
\n" ); document.write( "-9x+y = 71
\n" ); document.write( "--------------
\n" ); document.write( "0x + 4y = 32
\n" ); document.write( "y = 8
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