document.write( "Question 60688This question is from textbook Algebra & Trigonometry
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document.write( ": x+3=0
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document.write( "x+y+z=1
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document.write( "3x-y-z=11
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document.write( "We must use the Gauss-Jordan elimination.
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document.write( "I have already tried the problem with others and i keep getting the same wrong answer. the book says the answer is (3,-1,-1).
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document.write( "I did this:
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document.write( "1 3 0 / 0
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document.write( "1 1 1 / 1
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document.write( "3 -1 -1 / 11
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document.write( "then i did multiplied -1 to the first row and added to the second row. then multiplied -3 to the first row and added the product to the third row which gave me
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document.write( "1 3 0 / 0
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document.write( "0 -2 1 / 1
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document.write( "0 -10 -1 / 11
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document.write( "i then multiplied -1/2 to the second row which gives me
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document.write( "1 3 0 / 0
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document.write( "0 1 -1/2 / -1/2
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document.write( "0 -10 -1 / 11
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document.write( "them i multiplied 10 to the second row and added the product to the third row and got
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document.write( "1 3 0 / 0
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document.write( "0 1 -1/2 / -1/2
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document.write( "0 0 -6 / 16
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document.write( "by multiplying -1/6 to the third row gave me
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document.write( "1 3 0 / 0
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document.write( "0 1 -1/2 / -1/2
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document.write( "0 0 1 / -16/6
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document.write( "then i multiplied 1/2 to row 3 and added it to row 2 giving me
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document.write( "1 3 0 / 0
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document.write( "0 1 0 / -4/3
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document.write( "0 0 -6 / -16/6
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document.write( "then by multiplying -3 to the row 2 and adding that to row 1 i got
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document.write( "1 0 0 / 4
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document.write( "0 1 0 / -4/3
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document.write( "0 0 1 / -16/6
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document.write( "this give me the answer (4,-4/3,-16/6) which is clearly wrong. Could you look over my steps to see what i did wrong please?
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document.write( "
Algebra.Com's Answer #41658 by hayek(51)![]() ![]() ![]() You can put this solution on YOUR website! If the first equation is x+3y=0, then your error is in this step: \n" ); document.write( "them i multiplied 10 to the second row and added the product to the third row and got \n" ); document.write( "1 3 0 / 0 \n" ); document.write( "0 1 -1/2 / -1/2 \n" ); document.write( "0 0 -6 / 16\r \n" ); document.write( "\n" ); document.write( "The last number should be 11-5=6, not 16. \n" ); document.write( " |