document.write( "Question 146851: the solution set for x+y=2 and 2x+y=3 \n" ); document.write( "
Algebra.Com's Answer #107258 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%2By=2%2C2x%2By=3%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-2%28x%2By%29=-2%282%29\" Multiply the both sides of the first equation by -2.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x-2y=-4\" 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%28-2x-2y=-4%2C2x%2By=3%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( "\"%28-2x-2y%29%2B%282x%2By%29=%28-4%29%2B%283%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-2x%2B2x%29%2B%28-2y%2B1y%29=-4%2B3\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x-y=-1\" Combine like terms. Notice how the x terms cancel out.\r
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\n" ); document.write( "\n" ); document.write( "\"-y=-1\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%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=1\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x-2y=-4\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x-2%281%29=-4\" Plug in \"y=1\".\r
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\n" ); document.write( "\n" ); document.write( "\"-2x-2=-4\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x=-4%2B2\" Add \"2\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x=-2\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-2%29%2F%28-2%29\" Divide both sides by \"-2\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=1\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=1\" and \"y=1\".\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 two equations are 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%2By=2\" (red) and \"2x%2By=3\" (green) \r
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