document.write( "Question 342712: Solve the following system of linear equations,
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Algebra.Com's Answer #245272 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%28x%2B2y=5%2C2x%2By=-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( "\"2x%2By=-2\" Start with the second 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-2\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "Since \"y=-2x-2\", we can now replace each \"y\" in the first equation with \"-2x-2\" to solve for \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B2highlight%28%28-2x-2%29%29=5\" Plug in \"y=-2x-2\" into the first 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( "\"x%2B%282%29%28-2%29x%2B%282%29%28-2%29=5\" Distribute \"2\" to \"-2x-2\"\r
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\n" ); document.write( "\n" ); document.write( "\"x-4x-4=5\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"-3x-4=5\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"-3x=5%2B4\"Add 4 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"-3x=9\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%289%29%2F%28-3%29\" Divide both sides by -3 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=-3\" 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=-3\"\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"x=-3\" 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%28-3%29-2\" Plug in \"x=-3\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=6-2\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=4\" 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=4\"\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=-3\" and \"y=4\"\r
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\n" ); document.write( "\n" ); document.write( "which form the point \r
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\n" ); document.write( "\n" ); document.write( "If you need more help, email me at jim_thompson5910@hotmail.com\r
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\n" ); document.write( "\n" ); document.write( "Also, feel free to check out my tutoring website\r
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\n" ); document.write( "\n" ); document.write( "Jim
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