document.write( "Question 126070This question is from textbook algebra 1
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\n" ); document.write( " x=1-4y
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Algebra.Com's Answer #92382 by jim_thompson5910(35256)\"\" \"About 
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Start with the given system\r
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\n" ); document.write( "\n" ); document.write( "\"2%281-4y%29%2B7y=3\" Plug in \"x=1-4y\" into the first equation. In other words, replace each \"x\" with \"1-4y\". Notice we've eliminated the \"x\" variables. So we now have a simple equation with one unknown.\r
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\n" ); document.write( "\n" ); document.write( "\"2-8y%2B7y=3\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"-y%2B2=3\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"-y=3-2\"Subtract 2 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"-y=1\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"y=%281%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\" Divide\r
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\n" ); document.write( "\n" ); document.write( "Now that we know that \"y=-1\", we can plug this into \"x=1-4y\" to find \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=1-4%28-1%29\" Substitute \"-1\" for each \"y\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=5\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=5\" and \"y=-1\" 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+-4%2C+6%2C+-4%2C+6%2C+%283-2x%29%2F7%2C+%28x-1%29%2F%28-4%29%29+\" Graph of \"2x%2B7y=3\" (red) and \"x=1-4y\" (green)\r
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