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| Question 735913:  Please help me finish this problem
 Solve the system of equations using matrices. Thank you
 3x-y-2z=1
 4x+2y+z=5    >
 6x-2y-4z=9
 3 -1 -2=1
 4  2  1 = 5
 6 -2 -4=9
 R1=(1/3)R1
 1  (-1/3) -6=1/3
 4       2     1=5
 6     -2    -4=9
 R2=-4R1+r2
 1 (-1/3) -6=(1/3)
 0 (10/3) 25=(11/3)
 6  -2     -4=9
 
 Answer by MathLover1(20850)
      (Show Source): 
You can put this solution on YOUR website! given: 
   
   
 Row operation
 1:
 
 
  ....multiply the 1st row by 1/3 =>
   Row operation
 2:
 
  .........add -4 times the 1st row to the 2nd row...=>   
 Row operation
 3:
 
  ..............add -6 times the 1st row to the 3rd row=>..  . Row operation
 4:
 
  ....multiply the 2nd row by 3/10..=>...   Row operation
 5:
 
  ...........multiply the 3rd row by 1/7...=>...   Row operation
 6:
 
  .....add -11/10 times the 3rd row to the 2nd row...>...   
 Row operation
 7:
 
  ....add -1/3 times the 3rd row to the 1st row...=>...   Row operation
 8:
 matrix( 1,  	 -1 / 3,  	 -2 / 3,  	 0,
 0 , 	 1 , 	 11 / 10,  	 0,
 0,  	 0,  	 0,  	 1
 )
 )}}}.......add 1/3 times the 2nd row to the 1st row....=>
 matrix( 1,  	 0 , 	 -3/  10,  	 0
 0 , 	 1,  	 11/  10 , 	 0,
 0 , 	 0,  	 0,  	 1
 )
 )}}}
 
 so, your solutions ae:
  ,  , and  
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