document.write( "Question 127286: -5x+2y=-10
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Algebra.Com's Answer #93234 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%28-5x%2B2y=-10%2C3x-6y=-18%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( "\"-5x%2B2y=-10\" Start with the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"2y=-10%2B5x\" Add \"5x\" to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"2y=%2B5x-10\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28%2B5x-10%29%2F%282%29\" Divide both sides by \"2\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28%28%2B5%29%2F%282%29%29x%2B%28-10%29%2F%282%29\" Break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"y=%285%2F2%29x-5\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "Since \"y=%285%2F2%29x-5\", we can now replace each \"y\" in the second equation with \"%285%2F2%29x-5\" to solve for \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"3x-6highlight%28%28%285%2F2%29x-5%29%29=-18\" Plug in \"y=%285%2F2%29x-5\" into the first equation. In other words, replace each \"y\" with \"%285%2F2%29x-5\". 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%28-6%29%285%2F2%29x%2B%28-6%29%28-5%29=-18\" Distribute \"-6\" to \"%285%2F2%29x-5\"\r
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\n" ); document.write( "\n" ); document.write( "\"3x-%2830%2F2%29x%2B30=-18\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"%282%29%283x-%2830%2F2%29x%2B30%29=%282%29%28-18%29\" Multiply both sides by the LCM of 2. This will eliminate the fractions (note: if you need help with finding the LCM, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "\"6x-30x%2B60=-36\" Distribute and multiply the LCM to each side\r
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\n" ); document.write( "\n" ); document.write( "\"-24x%2B60=-36\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"-24x=-36-60\"Subtract 60 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"-24x=-96\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-96%29%2F%28-24%29\" Divide both sides by -24 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=4\" 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=4\"\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"x=4\" we can plug it into the equation \"y=%285%2F2%29x-5\" (remember we previously solved for \"y\" in the first equation).\r
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\n" ); document.write( "\n" ); document.write( "\"y=%285%2F2%29x-5\" Start with the equation where \"y\" was previously isolated.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%285%2F2%29%284%29-5\" Plug in \"x=4\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=20%2F2-5\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=5\" Combine like terms and reduce. (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=5\"\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=4\" and \"y=5\"\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 \"-5x%2B2y=-10\" (red) and \"3x-6y=-18\" (green) and the intersection of the lines (blue circle).\r
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