document.write( "Question 218305: Can someone explain the Gauss-Jordan elimination method to solve this system of linear equations?
\n" ); document.write( "2x+ y= 5
\n" ); document.write( "4x+ 3y= 11\r
\n" ); document.write( "\n" ); document.write( "Is the solution (2,1) or am I wrong? thank you.
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Algebra.Com's Answer #164394 by drj(1380)\"\" \"About 
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Can someone explain the Gauss-Jordan elimination method to solve this system of linear equations?\r
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\n" ); document.write( "\n" ); document.write( "2x+ y= 5 Equation A
\n" ); document.write( "4x+ 3y= 11 Equation B\r
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\n" ); document.write( "\n" ); document.write( "Is the solution (2,1) or am I wrong? thank you.\r
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\n" ); document.write( "\n" ); document.write( "Step 1 Check (2,1) by substituting into Equations A and B where x=2 and y=1.\r
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\n" ); document.write( "\n" ); document.write( "2*2+1= 5 or 5=5 which satisfies Equation A.\r
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\n" ); document.write( "\n" ); document.write( "4*2+3*1=8+3=11 of 11=11 which satisfies Equation B.\r
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\n" ); document.write( "\n" ); document.write( "Step 2. The elimination method in this example means when you multiply either Equation A or B by a factor such that when you add or subtract these two equations, one of the variables x or y will be eliminated. When you eliminate a variable, then you have an equation with one variable in this case.\r
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\n" ); document.write( "\n" ); document.write( "Step 3. As an example, take Equation A and multiply by -2. This yields\r
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\n" ); document.write( "\n" ); document.write( "\"-4x-2y=-10\" Equation A1
\n" ); document.write( "\"4x%2B3y=11\" Equation B\r
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\n" ); document.write( "\n" ); document.write( "Now when you add these two equations A1 and B, this will yield\r
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\n" ); document.write( "\n" ); document.write( "\"-4x%2B4x-2y%2B3y=-10%2B11\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=1\" This leaves a single equation with y=1.\r
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\n" ); document.write( "\n" ); document.write( "Step 4. As another example take Equation A and multiply by -3. This yields\r
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\n" ); document.write( "\n" ); document.write( "\"-6x-3y=-15\" Equation A2
\n" ); document.write( "\"4x%2B+3y=+11\" Equation B\r
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\n" ); document.write( "\n" ); document.write( "Adding these two Equations A2 and B yields\r
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\n" ); document.write( "\n" ); document.write( "\"-6x%2B4x-3y%2B3y=-15%2B11\"\r
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\n" ); document.write( "\n" ); document.write( "\"-2x=-4\" where we eliminated the y-terms and have a single variable in the equation.\r
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\n" ); document.write( "\n" ); document.write( "Now divide -2 to both sides of the equation\r
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\n" ); document.write( "\n" ); document.write( "\"x=2\"\r
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\n" ); document.write( "\n" ); document.write( "So the solution is x=2 and y=1 or at point (2,1) as a solution given earlier in the problem.\r
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\n" ); document.write( "\n" ); document.write( "I hope the above steps were helpful.\r
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\n" ); document.write( "\n" ); document.write( "For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.\r
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\n" ); document.write( "\n" ); document.write( "And good luck in your studies!\r
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\n" ); document.write( "\n" ); document.write( "Respectfully,
\n" ); document.write( "Dr J\r
\n" ); document.write( "\n" ); document.write( "http://www.FreedomUniversity.TV
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