document.write( "Question 165293: Solve by the substition method
\n" ); document.write( "8m+n=7
\n" ); document.write( "m-6n=56
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Algebra.Com's Answer #121853 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "Start with the given system of equations:\r
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\n" ); document.write( "\n" ); document.write( "\"system%288m%2Bn=7%2Cm-6n=56%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now in order to solve this system by using substitution, we need to solve (or isolate) one variable. I'm going to solve for n.\r
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\n" ); document.write( "\n" ); document.write( "So let's isolate n in the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"8m%2Bn=7\" Start with the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"n=7-8m\" Subtract \"8m\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"n=-8m%2B7\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "Since \"n=-8m%2B7\", we can now replace each \"n\" in the second equation with \"-8m%2B7\" to solve for \"m\"\r
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\n" ); document.write( "\n" ); document.write( "\"m-6highlight%28%28-8m%2B7%29%29=56\" Plug in \"n=-8m%2B7\" into the second equation. In other words, replace each \"n\" with \"-8m%2B7\". Notice we've eliminated the \"n\" variables. So we now have a simple equation with one unknown.\r
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\n" ); document.write( "\n" ); document.write( "\"m%2B%28-6%29%28-8%29m%2B%28-6%29%287%29=56\" Distribute \"-6\" to \"-8m%2B7\"\r
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\n" ); document.write( "\n" ); document.write( "\"m%2B48m-42=56\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"49m-42=56\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"49m=56%2B42\"Add 42 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"49m=98\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"m=%2898%29%2F%2849%29\" Divide both sides by 49 to isolate m\r
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\n" ); document.write( "\n" ); document.write( "\"m=2\" Divide\r
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\n" ); document.write( "\n" ); document.write( "-----------------First Answer------------------------------\r
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\n" ); document.write( "\n" ); document.write( "So the first part of our answer is: \"m=2\"\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"m=2\" we can plug it into the equation \"n=-8m%2B7\" (remember we previously solved for \"n\" in the first equation).\r
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\n" ); document.write( "\n" ); document.write( "\"n=-8m%2B7\" Start with the equation where \"n\" was previously isolated.\r
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\n" ); document.write( "\n" ); document.write( "\"n=-8%282%29%2B7\" Plug in \"m=2\"\r
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\n" ); document.write( "\n" ); document.write( "\"n=-16%2B7\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"n=-9\" Combine like terms \r
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\n" ); document.write( "\n" ); document.write( "-----------------Second Answer------------------------------\r
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\n" ); document.write( "\n" ); document.write( "So the second part of our answer is: \"n=-9\"\r
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\n" ); document.write( "\n" ); document.write( "-----------------Summary------------------------------\r
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\n" ); document.write( "\n" ); document.write( "So our answers are:\r
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\n" ); document.write( "\n" ); document.write( "\"m=2\" and \"n=-9\"\r
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\n" ); document.write( "\n" ); document.write( "which form the point
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