document.write( "Question 198292: I need help with this one that is using the substitution method. \r
\n" ); document.write( "\n" ); document.write( "7m+n=48
\n" ); document.write( "m-6n=13
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Algebra.Com's Answer #148733 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "Start with the given system of equations:\r
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\n" ); document.write( "\n" ); document.write( "\"system%287m%2Bn=48%2Cm-6n=13%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( "\"7m%2Bn=48\" Start with the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"n=48-7m\" Subtract \"7m\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"n=-7m%2B48\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "Since \"n=-7m%2B48\", we can now replace each \"n\" in the second equation with \"-7m%2B48\" to solve for \"m\"\r
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\n" ); document.write( "\n" ); document.write( "\"m-6highlight%28%28-7m%2B48%29%29=13\" Plug in \"n=-7m%2B48\" into the second equation. In other words, replace each \"n\" with \"-7m%2B48\". 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%28-7%29m%2B%28-6%29%2848%29=13\" Distribute \"-6\" to \"-7m%2B48\"\r
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\n" ); document.write( "\n" ); document.write( "\"m%2B42m-288=13\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"43m-288=13\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"43m=13%2B288\"Add 288 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"43m=301\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28301%29%2F%2843%29\" Divide both sides by 43 to isolate m\r
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\n" ); document.write( "\n" ); document.write( "\"m=7\" 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=7\"\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"m=7\" we can plug it into the equation \"n=-7m%2B48\" (remember we previously solved for \"n\" in the first equation).\r
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\n" ); document.write( "\n" ); document.write( "\"n=-7m%2B48\" Start with the equation where \"n\" was previously isolated.\r
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\n" ); document.write( "\n" ); document.write( "\"n=-7%287%29%2B48\" Plug in \"m=7\"\r
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\n" ); document.write( "\n" ); document.write( "\"n=-49%2B48\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"n=-1\" 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=-1\"\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=7\" and \"n=-1\"\r
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