document.write( "Question 112108: Solve the system of equations y=2x-10 and x-y=7 \n" ); document.write( "
Algebra.Com's Answer #81791 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Start with the given system\r
\n" ); document.write( "\n" ); document.write( "\"x-y=7\"
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\n" ); document.write( "\n" ); document.write( "\"x-%282x-10%29=7\" Plug in \"y=2x-10\" into the first equation. In other words, replace each \"y\" with \"2x-10\". 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-2x%2B10=7\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"-x%2B10=7\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"-x=7-10\"Subtract 10 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"-x=-3\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-3%29%2F%28-1%29\" Divide both sides by -1 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=3\" Divide\r
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\n" ); document.write( "\n" ); document.write( "Now that we know that \"x=3\", we can plug this into \"y=2x-10\" to find \"y\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=2%283%29-10\" Substitute \"3\" 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=3\" and \"y=-4\"
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