document.write( "Question 200627: Solve by the substitution method
\n" ); document.write( "7m+n=27
\n" ); document.write( "m-8n=69
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Algebra.Com's Answer #150881 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "Start with the given system of equations:\r
\n" ); document.write( "\n" ); document.write( "\"system%287m%2Bn=27%2Cm-8n=69%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"8%287m%2Bn%29=8%2827%29\" Multiply the both sides of the first equation by 8.\r
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\n" ); document.write( "\n" ); document.write( "\"56m%2B8n=216\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "So we have the new system of equations:\r
\n" ); document.write( "\n" ); document.write( "\"system%2856m%2B8n=216%2Cm-8n=69%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now add the equations together. You can do this by simply adding the two left sides and the two right sides separately like this:\r
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\n" ); document.write( "\n" ); document.write( "\"%2856m%2B8n%29%2B%28m-8n%29=%28216%29%2B%2869%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%2856m%2Bm%29%2B%288n-8n%29=216%2B69\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"57m%2B0n=285\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"57m=285\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28285%29%2F%2857%29\" Divide both sides by \"57\" to isolate \"m\".\r
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\n" ); document.write( "\n" ); document.write( "\"m=5\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"56m%2B8n=216\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"56%285%29%2B8n=216\" Plug in \"m=5\".\r
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\n" ); document.write( "\n" ); document.write( "\"280%2B8n=216\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"8n=216-280\" Subtract \"280\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"8n=-64\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"n=%28-64%29%2F%288%29\" Divide both sides by \"8\" to isolate \"n\".\r
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\n" ); document.write( "\n" ); document.write( "\"n=-8\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"m=5\" and \"n=-8\".\r
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\n" ); document.write( "\n" ); document.write( "This means that the system is consistent and independent.
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