document.write( "Question 127907: y=x-1
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Algebra.Com's Answer #93680 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "Start with the given system\r
\n" ); document.write( "\n" ); document.write( "\"2x-1y=0\"
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\n" ); document.write( "\n" ); document.write( "\"2x-1%28x-1%29=0\" Plug in \"y=x-1\" into the first equation. In other words, replace each \"y\" with \"x-1\". Notice we've eliminated the \"y\" variables. So we now have a simple equation with one unknown.\r
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\n" ); document.write( "\n" ); document.write( "\"2x-1x%2B1=0\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B1=0\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"x=0-1\"Subtract 1 from 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( "Now that we know that \"x=-1\", we can plug this into \"y=x-1\" to find \"y\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%29-1\" Substitute \"-1\" for each \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=-1\" and \"y=-2\" which also looks like \r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph the two equations, we can see that their intersection is at . So this verifies our answer.\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-5%2C+5%2C+-5%2C+5%2C+2x%2C+x-1%29+\" Graph of \"2x-1y=0\" (red) and \"y=x-1\" (green)\r
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