document.write( "Question 499795: Ive been working on a review for a test next tuesday, but i keep getting confused with this type of equation by using substitution.
\n" ); document.write( "{2x-y=2
\n" ); document.write( "{3x-2y=11
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Algebra.Com's Answer #337860 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%282x-y=2%2C3x-2y=11%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( "\"2x-y=2\" Start with the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"-y=2-2x\" Subtract \"2x\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"-y=-2x%2B2\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-2x%2B2%29%2F%28-1%29\" Divide both sides by \"-1\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28%28-2%29%2F%28-1%29%29x%2B%282%29%2F%28-1%29\" Break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"y=2x-2\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "Since \"y=2x-2\", we can now replace each \"y\" in the second equation with \"2x-2\" to solve for \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"3x-2highlight%28%282x-2%29%29=11\" Plug in \"y=2x-2\" into the second equation. In other words, replace each \"y\" with \"2x-2\". 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( "\"3x%2B%28-2%29%282%29x%2B%28-2%29%28-2%29=11\" Distribute \"-2\" to \"2x-2\"\r
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\n" ); document.write( "\n" ); document.write( "\"3x-4x%2B4=11\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"-x%2B4=11\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"-x=11-4\"Subtract 4 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"-x=7\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%287%29%2F%28-1%29\" Divide both sides by -1 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=-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: \"x=-7\"\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"x=-7\" we can plug it into the equation \"y=2x-2\" (remember we previously solved for \"y\" in the first equation).\r
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\n" ); document.write( "\n" ); document.write( "\"y=2x-2\" Start with the equation where \"y\" was previously isolated.\r
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\n" ); document.write( "\n" ); document.write( "\"y=2%28-7%29-2\" Plug in \"x=-7\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-14-2\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=-16\" 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=-16\"\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=-7\" and \"y=-16\"\r
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\n" ); document.write( "\n" ); document.write( "which form the point \r
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