document.write( "Question 422207: solve the system of equations by substitution
\n" ); document.write( "5x+y=-4
\n" ); document.write( "y=-x
\n" ); document.write( "

Algebra.Com's Answer #294713 by rfer(16322)\"\" \"About 
You can put this solution on YOUR website!
5x-x=-4
\n" ); document.write( "4x=-4
\n" ); document.write( "x=-1
\n" ); document.write( "------
\n" ); document.write( "5*-1+y=-4
\n" ); document.write( "-5+y=-4
\n" ); document.write( "y=+1
\n" ); document.write( "-------------
\n" ); document.write( "proof
\n" ); document.write( "y=-x
\n" ); document.write( "1=--1
\n" ); document.write( "
\n" );