document.write( "Question 93491: i have no idea how to start\r
\n" ); document.write( "\n" ); document.write( " X + 2y = -1
\n" ); document.write( " 2x - y = 8 \r
\n" ); document.write( "\n" ); document.write( "solve the system \n" ); document.write( "
Algebra.Com's Answer #68074 by checkley75(3666)\"\" \"About 
You can put this solution on YOUR website!
2X-Y=8
\n" ); document.write( "-Y=-2X+8
\n" ); document.write( "Y=2X-8 NOW REPLACE Y WITH (2X-8) IN THE OTHER EQUATION & SOLVE FOR X
\n" ); document.write( "X+2(2X-8)=-1
\n" ); document.write( "X+4X-16=-1
\n" ); document.write( "5X=-1+16
\n" ); document.write( "5X=15
\n" ); document.write( "X=15/5
\n" ); document.write( "X=3 ANSWER.
\n" ); document.write( "Y=2*3-8
\n" ); document.write( "Y=6-8
\n" ); document.write( "Y=-2 ANSWER.
\n" ); document.write( "PROOF
\n" ); document.write( "2*3-(-2)=8
\n" ); document.write( "6+2=8
\n" ); document.write( "8=8
\n" ); document.write( "-----------------------------------------------------------
\n" ); document.write( "OR YOU COULD USE THE ADDITION/SUBSTRATION METHOD:
\n" ); document.write( "MULTIPLY THE SECOND EQUATION BY 2 THUS:
\n" ); document.write( "4X-2Y=16 NOW ADD TO THE OTHER EQUATION:
\n" ); document.write( "X+2Y=-1
\n" ); document.write( "---------------------------------
\n" ); document.write( "5X=15
\n" ); document.write( "X=15/5
\n" ); document.write( "X=3 ANSWER.
\n" ); document.write( "3+2Y=-1
\n" ); document.write( "2Y=-1-3
\n" ); document.write( "2Y=-4
\n" ); document.write( "Y=-4/2
\n" ); document.write( "Y=-2 ANSWER.
\n" ); document.write( " \n" ); document.write( "
\n" );