document.write( "Question 360764: Solve the following system of equations. (this means – find the value for X and the value for Y - they should be the SAME for each equation!)You may use the elimination or substitution method:\r
\n" ); document.write( "\n" ); document.write( "x – y = 1\r
\n" ); document.write( "\n" ); document.write( "2x – y = 5
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Algebra.Com's Answer #257442 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "Start with the given system of equations:\r
\n" ); document.write( "\n" ); document.write( "\"system%28x-y=1%2C2x-y=5%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-1%282x-y%29=-1%285%29\" Multiply the both sides of the second equation by -1.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x%2By=-5\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "So we have the new system of equations:\r
\n" ); document.write( "\n" ); document.write( "\"system%28x-y=1%2C-2x%2By=-5%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now add the equations together. You can do this by simply adding the two left sides and the two right sides separately like this:\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-y%29%2B%28-2x%2By%29=%281%29%2B%28-5%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-2x%29%2B%28-y%2By%29=1-5\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"-x%2B0y=-4\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"-x=-4\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-4%29%2F%28-1%29\" Divide both sides by \"-1\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=4\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"x-y=1\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"4-y=1\" Plug in \"x=4\".\r
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\n" ); document.write( "\n" ); document.write( "\"-y=1-4\" Subtract \"4\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-y=-3\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-3%29%2F%28-1%29\" Divide both sides by \"-1\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=3\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=4\" and \"y=3\".\r
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\n" ); document.write( "\n" ); document.write( "Which form the ordered pair .\r
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\n" ); document.write( "\n" ); document.write( "This means that the system is consistent and independent.\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph the equations, we see that they intersect at . So this visually verifies our answer.\r
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\n" ); document.write( "\n" ); document.write( " Graph of \"x-y=1\" (red) and \"2x-y=5\" (green) \r
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\n" ); document.write( "\n" ); document.write( "If you need more help, email me at jim_thompson5910@hotmail.com\r
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\n" ); document.write( "\n" ); document.write( "Also, feel free to check out my tutoring website\r
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\n" ); document.write( "\n" ); document.write( "Jim
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