document.write( "Question 1139579: solve with substitution
\n" ); document.write( "x+y+z=15
\n" ); document.write( "2X-y+3z=-5
\n" ); document.write( "-x-y+z+-7 \n" ); document.write( "

Algebra.Com's Answer #760061 by Alan3354(69443) $\"\"$ $\"About$

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solve with substitution
\n" ); document.write( "x+y+z=15
\n" ); document.write( "2X-y+3z=-5
\n" ); document.write( "-x-y+z+-7
\n" ); document.write( "========================
\n" ); document.write( "The 3rd row has no equal sign.
\n" ); document.write( "I'll assume you meant:
\n" ); document.write( "solve with substitution
\n" ); document.write( "x+y+z=15
\n" ); document.write( "2X-y+3z=-5
\n" ); document.write( "-x-y+z = -7
\n" ); document.write( "--------------
\n" ); document.write( "x + y + z = 15
\n" ); document.write( "2x -y +3z = -5
\n" ); document.write( "-x - y + z = -7
\n" ); document.write( "=====================
\n" ); document.write( "Add eqns 1 & 3
\n" ); document.write( "2z = 8
\n" ); document.write( "z = 4
\n" ); document.write( "==============
\n" ); document.write( "Sub for z in eqns 1 & 2
\n" ); document.write( "---
\n" ); document.write( "x + y + 4 = 15 ------------- Eqn A
\n" ); document.write( "2x -y +12 = -5
\n" ); document.write( "----------------------- Add
\n" ); document.write( "3x + 16 = 10
\n" ); document.write( "3x = -6
\n" ); document.write( "x = -2
\n" ); document.write( "----------------
\n" ); document.write( "Sub for x in eqn A
\n" ); document.write( "x + y + 4 = 15
\n" ); document.write( "-2 + y + 4 = 15
\n" ); document.write( "y = 13
\n" ); document.write( "(-2,13,4)\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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