document.write( "Question 175920: Solve each system by addition\r
\n" ); document.write( "\n" ); document.write( "x-2y=-1
\n" ); document.write( "-x+5y=4\r
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Algebra.Com's Answer #131034 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
I'll do the first one to get you going in the right direction\r
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\n" ); document.write( "\n" ); document.write( "Start with the given system of equations:\r
\n" ); document.write( "\n" ); document.write( "\"system%28x-2y=-1%2C-x%2B5y=4%29\"\r
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\n" ); document.write( "\n" ); document.write( "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-2y%29%2B%28-x%2B5y%29=%28-1%29%2B%284%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-x%29%2B%28-2y%2B5y%29=-1%2B4\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B3y=3\" Combine like terms. Notice how the x terms cancel out.\r
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\n" ); document.write( "\n" ); document.write( "\"3y=3\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%283%29%2F%283%29\" Divide both sides by \"3\" 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( "\"x-2y=-1\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"x-2%281%29=-1\" Plug in \"y=1\".\r
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\n" ); document.write( "\n" ); document.write( "\"x-2=-1\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"x=-1%2B2\" Add \"2\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x=1\" Combine like terms on the right side.\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 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-2y=-1\" (red) and \"-x%2B5y=4\" (green)
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