document.write( "Question 849834: i don't have any idea in solving this elimination method. Can you help me? Please
\n" ); document.write( "3x+5y-2z=7
\n" ); document.write( "5x+4y+5z=-13
\n" ); document.write( "3x-2y+4z=-3
\n" ); document.write( "Please help me. \n" ); document.write( "

Algebra.Com's Answer #511831 by Fombitz(32388) $\"\"$ $\"About$

You can put this solution on YOUR website!
1. $\"3x%2B5y-2z=7\"$
\n" ); document.write( "2. $\"5x%2B4y%2B5z=-13\"$
\n" ); document.write( "3. $\"3x-2y%2B4z=-3\"$
\n" ); document.write( "Subtract eq. 3 from eq. 1,
\n" ); document.write( " $\"3x%2B5y-2z-3x%2B2y-4z=7%2B3\"$
\n" ); document.write( "4. $\"7y-6z=10\"$
\n" ); document.write( "Multiply eq. 1 by 5 and eq. 2 by -3 and add them,
\n" ); document.write( " $\"15x%2B25y-10z-15x-12y-15z=35%2B39\"$
\n" ); document.write( "5. $\"13y-25z=74\"$
\n" ); document.write( "Now x is elmininated.
\n" ); document.write( "Multiply eq. 4 by 13 and eq. 5 by (-7) and add them,
\n" ); document.write( " $\"91y-78z-91y%2B175z=130-518\"$
\n" ); document.write( " $\"97z=-388\"$
\n" ); document.write( " $\"z=-4\"$
\n" ); document.write( "Now back substitute to find $\"y\"$
\n" ); document.write( " $\"7y-6%28-4%29=10\"$
\n" ); document.write( " $\"7y=-14\"$
\n" ); document.write( " $\"y=-2\"$
\n" ); document.write( "and finally,
\n" ); document.write( " $\"3x%2B5%28-2%29-2%28-4%29=7\"$
\n" ); document.write( " $\"3x-10%2B8=7\"$
\n" ); document.write( " $\"3x=9\"$
\n" ); document.write( " $\"x=3\"$ \n" ); document.write( "

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