document.write( "Question 203073: -3x+y=3 and 2x-y=-1
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Algebra.Com's Answer #153190 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"system%28-3x%2By=3%2C2x-y=-1%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-3x%2By=3\" Start with the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=3%2B3x\" Add \"3x\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y=3x%2B3\" Rearrange the terms and simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"2x-y=-1\" Move onto the second equation.\r
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\n" ); document.write( "\n" ); document.write( "\"2x-%283x%2B3%29=-1\" Now plug in \"y=3x%2B3\".\r
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\n" ); document.write( "\n" ); document.write( "\"2x-3x-3=-1\" Distribute.\r
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\n" ); document.write( "\n" ); document.write( "\"-x-3=-1\" Combine like terms on the left side.\r
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\n" ); document.write( "\n" ); document.write( "\"-x=-1%2B3\" Add \"3\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-x=2\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%282%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=-2\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"x=-2\", we can use this to find \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"-3x%2By=3\" Go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-3%28-2%29%2By=3\" Plug in \"x=-2\".\r
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\n" ); document.write( "\n" ); document.write( "\"6%2By=3\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"y=3-6\" Subtract \"6\" 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( "So the solutions are \"x=-2\" and \"y=-3\".\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 \"-3x%2By=3\" (red) and \"2x-y=-1\" (green) \r
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