document.write( "Question 126485: Solve using REF\r
\n" ); document.write( "\n" ); document.write( "x-y-2z=0
\n" ); document.write( "-2x+5y+10z=-3
\n" ); document.write( "3x+y=0\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

Algebra.Com's Answer #92673 by MathLover1(20850) $\"\"$ $\"About$

You can put this solution on YOUR website!
\r
\n" ); document.write( "\n" ); document.write( " $\"x-y-2z=0\"$ ЕЕЕЕЕЕЕЕЕЕЕЕ(1)\r
\n" ); document.write( "\n" ); document.write( " $\"-2x%2B5y%2B10z=-3\"$ ЕЕЕЕЕЕЕЕЕ.(2)\r
\n" ); document.write( "\n" ); document.write( " $\"3x%2By=0\"$ ЕЕЕЕЕЕЕЕЕЕЕЕ..(3)
\n" ); document.write( "
\n" ); document.write( "---------------------------------------------------------------\r
\n" ); document.write( "\n" ); document.write( " $\"x-y-2z=0\"$ ЕЕЕЕЕЕЕЕЕЕЕЕ(1)Е=>\r
\n" ); document.write( "\n" ); document.write( " $\"x+=+y+%2B+2z\"$ ЕЕЕЕЕЕplug into (2)\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"-2%28y+%2B+2z+%29+%2B+5y+%2B+10z+=+-3\"$ ЕЕЕЕЕЕЕЕЕ.(2)\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"-2y+-+4z++%2B+5y+%2B+10z+=+-3\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"3y+%2B+6z+=+-3\"$ ЕЕЕЕЕЕЕЕЕ(I)\r
\n" ); document.write( "\n" ); document.write( "Now plug $\"x\"$ into (3)\r
\n" ); document.write( "\n" ); document.write( " $\"3%28y+%2B+2z+%29%2By=0\"$ ЕЕЕЕЕЕЕЕЕЕЕЕ..(3)\r
\n" ); document.write( "\n" ); document.write( " $\"3y+%2B+6z+%2By=0\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"4y+%2B+6z+=0\"$ ЕЕЕЕЕЕЕЕЕЕ..(II)\r
\n" ); document.write( "\n" ); document.write( "subtract (II) from (I) to solve for $\"y\"$ \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"3y+%2B+6z+=+-3\"$ ЕЕЕЕЕЕЕЕЕ(I)
\n" ); document.write( " $\"4y+%2B+6z+=0\"$ ЕЕЕЕЕЕЕЕЕЕ..(II)
\n" ); document.write( "-----------------------------------------------------------
\n" ); document.write( " $\"3y-4y%2B6z-6z=+-3+%96+0\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"-y%2Bcross%286z%29-cross%286z%29+=+-3+\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"highlight%28y+=+3%29+\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"3x%2By=0\"$ ЕЕЕЕЕЕЕЕЕЕЕЕ..(3)Еplug in $\"y\"$ and find $\"x\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"3x%2B3=0\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"3x+=+-3\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"highlight%28x+=+-1%29\"$ \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"x-y-2z=0\"$ ЕЕЕЕЕЕЕЕЕЕЕЕ(1)Е.. plug in $\"x\"$ and $\"y\"$ , then find $\"z\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"-1-3-2z=0\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"-4-2z=0\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"-4+=+2z\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"-4%2F2+=+z\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"highlight%28z+=+-2%29+\"$ \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Check:\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"x-y-2z=0\"$ ЕЕЕЕЕЕЕЕЕЕЕЕ(1)\r
\n" ); document.write( "\n" ); document.write( " $\"-1-3-2%28-2%29+=+0\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"-4+%2B+4+=+0\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"0+=+0\"$ \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"-2x%2B5y%2B10z=-3\"$ ЕЕЕЕЕЕЕЕЕ.(2)\r
\n" ); document.write( "\n" ); document.write( " $\"-2%28-1%29%2B5%2A3%2B10%28-2%29+=-3\"$
\n" ); document.write( "
\n" ); document.write( " $\"2+%2B+15++-20+=+-3\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"+17++-20+=+-3\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"+-3++=+-3\"$ \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"3x%2By=0\"$ ЕЕЕЕЕЕЕЕЕЕЕЕ..(3)\r
\n" ); document.write( "\n" ); document.write( " $\"3%28-1%29+%2B+3+=+0\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"-3+%2B+3+=+0\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"0+=+0\"$ \r
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( " \n" ); document.write( "

\n" );