document.write( "Question 116202: Please help.\r
\n" ); document.write( "\n" ); document.write( "Solve the system by substitution.\r
\n" ); document.write( "\n" ); document.write( "4x+2y=8
\n" ); document.write( " y=-3x+7\r
\n" ); document.write( "\n" ); document.write( "Thanks
\n" ); document.write( "JMS
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Algebra.Com's Answer #84507 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "Start with the given system\r
\n" ); document.write( "\n" ); document.write( "\"4x%2B2y=8\"
\n" ); document.write( "\"y=-3x%2B7\"\r
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\n" ); document.write( "\n" ); document.write( "\"4x%2B2%28-3x%2B7%29=8\" Plug in \"y=-3x%2B7\" into the first equation. In other words, replace each \"y\" with \"-3x%2B7\". 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( "\"4x%2B-6x%2B14=8\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"-2x%2B14=8\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"-2x=8-14\"Subtract 14 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"-2x=-6\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-6%29%2F%28-2%29\" Divide both sides by -2 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=-3x%2B7\" to find \"y\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-3%283%29%2B7\" Substitute \"3\" for each \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=3\" and \"y=-2\"
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