document.write( "Question 407511: solve by the substatution method\r
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Algebra.Com's Answer #287281 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"system%28-2x%2By=19%2C2x%2B4y=26%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=19\" Start with the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=19%2B2x\" Add \"2x\" to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"y=2x%2B19\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "Since \"y=2x%2B19\", we can now replace each \"y\" in the second equation with \"2x%2B19\" to solve for \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"2x%2B4highlight%28%282x%2B19%29%29=26\" Plug in \"y=2x%2B19\" into the second equation. In other words, replace each \"y\" with \"2x%2B19\". 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( "\"2x%2B%284%29%282%29x%2B%284%29%2819%29=26\" Distribute \"4\" to \"2x%2B19\"\r
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\n" ); document.write( "\n" ); document.write( "\"2x%2B8x%2B76=26\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"10x%2B76=26\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"10x=26-76\"Subtract 76 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"10x=-50\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-50%29%2F%2810%29\" Divide both sides by 10 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=-5\" 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=-5\"\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"x=-5\" we can plug it into the equation \"y=2x%2B19\" (remember we previously solved for \"y\" in the first equation).\r
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\n" ); document.write( "\n" ); document.write( "\"y=2x%2B19\" Start with the equation where \"y\" was previously isolated.\r
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\n" ); document.write( "\n" ); document.write( "\"y=2%28-5%29%2B19\" Plug in \"x=-5\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-10%2B19\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=9\" 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=9\"\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=-5\" and \"y=9\"\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( "Now let's graph the two equations (if you need help with graphing, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "From the graph, we can see that the two equations intersect at . This visually verifies our answer.\r
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\n" ); document.write( "\n" ); document.write( " graph of \"-2x%2By=19\" (red) and \"2x%2B4y=26\" (green) and the intersection of the lines (blue circle).\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, please consider visiting my website: http://www.freewebs.com/jimthompson5910/home.html and making a donation. Thank you\r
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