document.write( "Question 144159: y=x+3
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Algebra.Com's Answer #104926 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Start with the given system\r
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\n" ); document.write( "\n" ); document.write( "\"8x-7%28x%2B3%29=12\" Plug in \"y=x%2B3\" into the first equation. In other words, replace each \"y\" with \"x%2B3\". 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( "\"8x-7x-21=12\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"x-21=12\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"x=12%2B21\"Add 21 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"x=33\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "Now that we know that \"x=33\", we can plug this into \"y=x%2B3\" to find \"y\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%2833%29%2B3\" Substitute \"33\" for each \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=36\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "So our answers are \"x=33\" and \"y=36\"
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