document.write( "Question 715196: x-2y+3z=11
\n" ); document.write( "4x+2y-3z=4
\n" ); document.write( "3x+3y-z=4
\n" ); document.write( " Using equations 1 and 2, and 1 and 3, elimiate x first and solve. \r
\n" ); document.write( "\n" ); document.write( "I can elimiate the x, but once i get to the equation
\n" ); document.write( "10y-15z=-40
\n" ); document.write( "9y-10z=-29\r
\n" ); document.write( "\n" ); document.write( "I get stumped. I know the solution is (3,-1,2) But I cannot get it to work. Please help by walking me though it.
\n" ); document.write( "Thanks!
\n" ); document.write( "

Algebra.Com's Answer #439279 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
(1) \"+x+-+2y+%2B+3z+=+11+\"
\n" ); document.write( "(2) \"+4x+%2B+2y+-+3z+=+4+\"
\n" ); document.write( "(3) \"+3x+%2B+3y+-+z+=+4+\"
\n" ); document.write( "Add equations (1) and (2)
\n" ); document.write( "(1) \"+x+-+2y+%2B+3z+=+11+\"
\n" ); document.write( "(2) \"+4x+%2B+2y+-+3z+=+4+\"
\n" ); document.write( "\"+5x+=+15+\"
\n" ); document.write( "\"+x+=+3+\"
\n" ); document.write( "Plug this result into both (2) and (3)
\n" ); document.write( "(2) \"+4%2A3+%2B+2y+-+3z+=+4+\"
\n" ); document.write( "(3) \"+3%2A3+%2B+3y+-+z+=+4+\"
\n" ); document.write( "----------------------
\n" ); document.write( "(2) \"+12+%2B+2y+-+3z+=+4+\"
\n" ); document.write( "(3) \"+9+%2B+3y+-+z+=+4+\"
\n" ); document.write( "--------------------
\n" ); document.write( "(2) \"+2y+-+3z+=+-8+\"
\n" ); document.write( "(3) \"+3y+-+z+=+-5+\"
\n" ); document.write( "-----------------
\n" ); document.write( "Multiply both sides of (3) by \"+-3+\"
\n" ); document.write( "and add (2) and (3)
\n" ); document.write( "(2) \"+2y+-+3z+=+-8+\"
\n" ); document.write( "(3) \"+-9y+%2B+3z+=+15+\"
\n" ); document.write( "\"+-7y+=+7+\"
\n" ); document.write( "\"+y+=+-1+\"
\n" ); document.write( "----------
\n" ); document.write( "Plug this result into (2) or (3)
\n" ); document.write( "(2) \"+2y+-+3z+=+-8+\"
\n" ); document.write( "(2) \"+2%2A%28-1%29+-+3z+=+-8+\"
\n" ); document.write( "(2) \"+-2+-+3z+=+-8+\"
\n" ); document.write( "(2) \"+-3z+=+-6+\"
\n" ); document.write( "(2) \"+z+=+2+\"
\n" ); document.write( "--------------
\n" ); document.write( "\"+x+=+3+\"
\n" ); document.write( "\"+y+=+-1+\"
\n" ); document.write( "\"+z+=+2+\"\r
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