document.write( "Question 795658: These are solutions of three equations in three variables. i don't understand this at all. can someone please help? \r
\n" ); document.write( "\n" ); document.write( "Solve the system:
\n" ); document.write( "2x+y+4z=16
\n" ); document.write( "x+2y+2z=11
\n" ); document.write( "3x-3y-2z= -9\r
\n" ); document.write( "\n" ); document.write( "PLEASE HELP AND SHOW WORK!!!! \n" ); document.write( "

Algebra.Com's Answer #481100 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
You have 3 equations and 3 unknowns,
\n" ); document.write( "and this means that the system is solvable.
\n" ); document.write( "You can find out the numbers that
\n" ); document.write( "x,y, and z actually represent.
\n" ); document.write( "------------------------------
\n" ); document.write( "(1) $\"+2x%2By%2B4z=16+\"$
\n" ); document.write( "(2) $\"+x%2B2y%2B2z=11+\"$
\n" ); document.write( "(3) $\"+3x-3y-2z=+-9+\"$
\n" ); document.write( "--------------------
\n" ); document.write( "Add (2) and (3)
\n" ); document.write( " $\"+4x+-+y+=+2+\"$
\n" ); document.write( " $\"+y+=+4x+-+2+\"$
\n" ); document.write( "--------------
\n" ); document.write( "Plug this value of $\"+y+\"$ into (1)
\n" ); document.write( "(1) $\"+2x+%2B+4x+-+2+%2B+4z+=+16+\"$
\n" ); document.write( "(1) $\"+6x+%2B+4z+=+18+\"$
\n" ); document.write( "(1) $\"+3x+%2B+2z+=+9+\"$
\n" ); document.write( "(1) $\"+2z+=+-3x+%2B+9+\"$
\n" ); document.write( "-------------------
\n" ); document.write( "There is a $\"+2z+\"$ in equation (2), so I
\n" ); document.write( "can plug this into (2)
\n" ); document.write( "I also have $\"+y+=+4x+-+2+\"$ that I can plug into (2)
\n" ); document.write( "-------------------
\n" ); document.write( "(2) $\"+x%2B2y%2B2z=11+\"$
\n" ); document.write( "(2) $\"+x%2B2%2A%28+4x-2+%29%2B%28+-3x+%2B+9+%29+=11+\"$
\n" ); document.write( "(2) $\"+x+%2B+8x+-+4+-+3x+%2B+9+=+11+\"$
\n" ); document.write( "(2) $\"+6x+-+13+=+11+\"$
\n" ); document.write( "(2) $\"+6x+=+24+\"$
\n" ); document.write( "(2) $\"+x+=+4+\"$
\n" ); document.write( "---------------
\n" ); document.write( "Now the other dominoes just fall
\n" ); document.write( " $\"+y+=+4x+-+2+\"$
\n" ); document.write( " $\"+y+=+4%2A4+-+2+\"$
\n" ); document.write( " $\"+y+=+16+-+2+\"$
\n" ); document.write( " $\"+y+=+14+\"$
\n" ); document.write( "and
\n" ); document.write( "(1) $\"+2z+=+-3x+%2B+9+\"$
\n" ); document.write( "(1) $\"+2z+=+-3%2A4+%2B+9+\"$
\n" ); document.write( "(1) $\"+2z+=+-12+%2B+9+\"$
\n" ); document.write( "(1) $\"+2z+=+-3+\"$
\n" ); document.write( "(1) $\"+z+=+-3%2F2+\"$
\n" ); document.write( "------------------
\n" ); document.write( "check answers:
\n" ); document.write( "(1) $\"+2x%2By%2B4z=16+\"$
\n" ); document.write( "(1) $\"+2%2A4+%2B+14+%2B+4%2A%28-3%2F2%29+=+16+\"$
\n" ); document.write( "(1) $\"+8+%2B+14+-+6+=+16+\"$
\n" ); document.write( "(1) $\"+22+-+6+=+16+\"$
\n" ); document.write( "(1) $\"+16+=+16+\"$
\n" ); document.write( "--------------
\n" ); document.write( "You can check (2) and (3)\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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