document.write( "Question 182101This question is from textbook Saxon
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\n" ); document.write( "\n" ); document.write( "x= 3y+6
\n" ); document.write( "2x+y= -16\r
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Algebra.Com's Answer #136676 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( "\"x=3y%2B6\"
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\n" ); document.write( "\n" ); document.write( "\"2%283y%2B6%29%2By=-16\" Plug in \"x=3y%2B6\" into the second equation. In other words, replace each \"x\" with \"3y%2B6\". 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( "\"6y%2B12%2By=-16\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"7y%2B12=-16\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"7y=-16-12\"Subtract 12 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"7y=-28\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-28%29%2F%287%29\" Divide both sides by 7 to isolate y\r
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\n" ); document.write( "\n" ); document.write( "\"y=-4\" Divide\r
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\n" ); document.write( "\n" ); document.write( "Now that we know that \"y=-4\", we can plug this into \"x=3y%2B6\" to find \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=3%28-4%29%2B6\" Substitute \"-4\" for each \"y\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=-12%2B6\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"x=-6\" Add\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=-6\" and \"y=-4\" which form the ordered pair \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+-10%2C+10%2C+-10%2C+10%2C+%28x-6%29%2F3%2C+%28-16-2x%29%2F1%29+\" Graph of \"x=3y%2B6\" (red) and \"2x%2By=-16\" (green)\r
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