document.write( "Question 44742This question is from textbook College Algebra
\n" ); document.write( ": Solve each system using Gaussian elimination. State whether each system is independent, inconsistent, or dependent. \n" ); document.write( "
Algebra.Com's Answer #29595 by Nazareth(2)\"\" \"About 
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Elimination Method\r
\n" ); document.write( "\n" ); document.write( "3x - 6y = 9.....multiply this line by 2
\n" ); document.write( "2x + y = -4.....mutiply by 3\r
\n" ); document.write( "\n" ); document.write( "We have:
\n" ); document.write( "6x - 12y = 18...(1)
\n" ); document.write( "6x + 3y = -12...(2)\r
\n" ); document.write( "\n" ); document.write( "we work by eliminating x therefore (1) - (2)
\n" ); document.write( "We have:\r
\n" ); document.write( "\n" ); document.write( "6x - 6x = 0\r
\n" ); document.write( "\n" ); document.write( "-12y -3y = -15y\r
\n" ); document.write( "\n" ); document.write( "and 18 - (-12)= 30\r
\n" ); document.write( "\n" ); document.write( "This give -15y = 30\r
\n" ); document.write( "\n" ); document.write( "Divide both side by -15, we have:
\n" ); document.write( "y = -2\r
\n" ); document.write( "\n" ); document.write( "Replcing the value of y in any of the above equation:\r
\n" ); document.write( "\n" ); document.write( "for example
\n" ); document.write( "we use
\n" ); document.write( "3x -6y=9
\n" ); document.write( "3x - 6(-2) = 9
\n" ); document.write( "3x +12 = 9, since - x - = +\r
\n" ); document.write( "\n" ); document.write( "then take away 12 from both sides, leaving
\n" ); document.write( "3x = - 3\r
\n" ); document.write( "\n" ); document.write( "giving x = -1\r
\n" ); document.write( "\n" ); document.write( "Answer:
\n" ); document.write( "x = -1
\n" ); document.write( "y = -2
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