document.write( "Question 127880: -4x-6y=7
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Algebra.Com's Answer #93663 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Do you want to solve using substitution?\r
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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%28-4x-6y=7%2Cx%2B5y=8%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 y.\r
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\n" ); document.write( "\n" ); document.write( "So let's isolate y in the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"-4x-6y=7\" Start with the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"-6y=7%2B4x\" Add \"4x\" to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"-6y=%2B4x%2B7\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28%2B4x%2B7%29%2F%28-6%29\" Divide both sides by \"-6\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28%28%2B4%29%2F%28-6%29%29x%2B%287%29%2F%28-6%29\" Break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-2%2F3%29x-7%2F6\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "Since \"y=%28-2%2F3%29x-7%2F6\", we can now replace each \"y\" in the second equation with \"%28-2%2F3%29x-7%2F6\" to solve for \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B5highlight%28%28%28-2%2F3%29x-7%2F6%29%29=8\" Plug in \"y=%28-2%2F3%29x-7%2F6\" into the first equation. In other words, replace each \"y\" with \"%28-2%2F3%29x-7%2F6\". 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%2B%285%29%28-2%2F3%29x%2B%285%29%28-7%2F6%29=8\" Distribute \"5\" to \"%28-2%2F3%29x-7%2F6\"\r
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\n" ); document.write( "\n" ); document.write( "\"x-%2810%2F3%29x-35%2F6=8\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"%286%29%281x-%2810%2F3%29x-35%2F6%29=%286%29%288%29\" Multiply both sides by the LCM of 6. This will eliminate the fractions (note: if you need help with finding the LCM, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "\"6x-20x-35=48\" Distribute and multiply the LCM to each side\r
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\n" ); document.write( "\n" ); document.write( "\"-14x-35=48\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"-14x=48%2B35\"Add 35 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"-14x=83\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2883%29%2F%28-14%29\" Divide both sides by -14 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=-83%2F14\" Reduce\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: \"x=-83%2F14\"\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"x=-83%2F14\" we can plug it into the equation \"y=%28-2%2F3%29x-7%2F6\" (remember we previously solved for \"y\" in the first equation).\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-2%2F3%29x-7%2F6\" Start with the equation where \"y\" was previously isolated.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-2%2F3%29%28-83%2F14%29-7%2F6\" Plug in \"x=-83%2F14\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=166%2F42-7%2F6\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=39%2F14\" Combine like terms and reduce. (note: if you need help with fractions, check out this solver)\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: \"y=39%2F14\"\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( "\"x=-83%2F14\" and \"y=39%2F14\"\r
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\n" ); document.write( "\n" ); document.write( "which form the point \r
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