document.write( "Question 115283: x=3y+7
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Algebra.Com's Answer #83869 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( "\"%283y%2B7%29%2By=-5\" Plug in \"x=3y%2B7\" into the first equation. In other words, replace each \"x\" with \"3y%2B7\". 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( "\"4y%2B7=-5\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"4y=-5-7\"Subtract 7 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"4y=-12\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-12%29%2F%284%29\" Divide both sides by 4 to isolate y\r
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\n" ); document.write( "\n" ); document.write( "\"y=-3\" Divide\r
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\n" ); document.write( "\n" ); document.write( "Now that we know that \"y=-3\", we can plug this into \"x=3y%2B7\" to find \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=3%28-3%29%2B7\" Substitute \"-3\" for each \"y\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=-2\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=-2\" and \"y=-3\"
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