document.write( "Question 144053: x - y = -5
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Algebra.Com's Answer #104840 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Do you want to use substitution to solve this system.\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%28x-y=-5%2Cx%2B2y=-4%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( "\"x-y=-5\" Start with the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"-y=-5-x\" Subtract \"x\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"-y=-x-5\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-x-5%29%2F%28-1%29\" Divide both sides by \"-1\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28%28-1%29%2F%28-1%29%29x%2B%28-5%29%2F%28-1%29\" Break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"y=x%2B5\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "Since \"y=x%2B5\", we can now replace each \"y\" in the second equation with \"x%2B5\" to solve for \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B2highlight%28%28x%2B5%29%29=-4\" Plug in \"y=x%2B5\" into the first equation. In other words, replace each \"y\" with \"x%2B5\". 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%282%29%281%29x%2B%282%29%285%29=-4\" Distribute \"2\" to \"x%2B5\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B2x%2B10=-4\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"3x%2B10=-4\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"3x=-4-10\"Subtract 10 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"3x=-14\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-14%29%2F%283%29\" Divide both sides by 3 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=-14%2F3\" 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=-14%2F3\"\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"x=-14%2F3\" we can plug it into the equation \"y=x%2B5\" (remember we previously solved for \"y\" in the first equation).\r
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\n" ); document.write( "\n" ); document.write( "\"y=x%2B5\" Start with the equation where \"y\" was previously isolated.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-14%2F3%29%2B5\" Plug in \"x=-14%2F3\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-14%2F3%2B5\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=1%2F3\" Combine like terms (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=1%2F3\"\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=-14%2F3\" and \"y=1%2F3\"
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