document.write( "Question 120342: which equation is bets use for the problem y=-x+6 and x-2y=-6 \n" ); document.write( "
Algebra.Com's Answer #88213 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "Start with the given system\r
\n" ); document.write( "\n" ); document.write( "\"x-2y=-6\"
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\n" ); document.write( "\n" ); document.write( "\"x-2%28-x%2B6%29=-6\" Plug in \"y=-x%2B6\" into the first equation. In other words, replace each \"y\" with \"-x%2B6\". 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( "\"x%2B2x-12=-6\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"3x-12=-6\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"3x=-6%2B12\"Add 12 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"3x=6\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%286%29%2F%283%29\" Divide both sides by 3 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=2\" Divide\r
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\n" ); document.write( "\n" ); document.write( "Now that we know that \"x=2\", we can plug this into \"y=-1x%2B6\" to find \"y\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-1%282%29%2B6\" Substitute \"2\" for each \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=4\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=2\" and \"y=4\" 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+%28-6-x%29%2F-2%2C+-x%2B6%29+\" Graph of \"x-2y=-6\" (red) and \"y=-x%2B6\" (green)\r
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