document.write( "Question 175915: Solve each system by the substitution method.\r
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Algebra.Com's Answer #131027 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"system%28-x%2By=1%2Cx%2B3y=2%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%2By=1\" Start with the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=1%2Bx\" Add \"x\" to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"y=%2Bx%2B1\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "Since \"y=x%2B1\", we can now replace each \"y\" in the second equation with \"x%2B1\" to solve for \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B3highlight%28%28x%2B1%29%29=2\" Plug in \"y=x%2B1\" into the second equation. In other words, replace each \"y\" with \"x%2B1\". 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%283%29%281%29x%2B%283%29%281%29=2\" Distribute \"3\" to \"x%2B1\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B3x%2B3=2\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"4x%2B3=2\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"4x=2-3\"Subtract 3 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"4x=-1\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-1%29%2F%284%29\" Divide both sides by 4 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=-1%2F4\" 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=-1%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"x=-1%2F4\" we can plug it into the equation \"y=x%2B1\" (remember we previously solved for \"y\" in the first equation).\r
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\n" ); document.write( "\n" ); document.write( "\"y=x%2B1\" Start with the equation where \"y\" was previously isolated.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-1%2F4%2B1\" Plug in \"x=-1%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=3%2F4\" 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: \"y=3%2F4\"\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=-1%2F4\" and \"y=3%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "which form the ordered pair \r
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