document.write( "Question 124657: The sum of two numbers is 38. Their difference is 10. What are the two numbers?
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Algebra.Com's Answer #91377 by jim_thompson5910(35256)\"\" \"About 
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The sentence \"The sum of two numbers is 38\" translates to the equation \"x%2By=38\"\r
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\n" ); document.write( "\n" ); document.write( "The sentence \"Their difference is 10\" translates to the equation \"x-y=10\"\r
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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%2By=38%2Cx-y=10%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=38\" Start with the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=38-x\" Subtract \"x\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"y=-x%2B38\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-x%2B38%29%2F%281%29\" Divide both sides by \"1\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28%28-1%29%2F%281%29%29x%2B%2838%29%2F%281%29\" Break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"y=-x%2B38\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "Since \"y=-x%2B38\", we can now replace each \"y\" in the second equation with \"-x%2B38\" to solve for \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"x-highlight%28%28-x%2B38%29%29=10\" Plug in \"y=-x%2B38\" into the first equation. In other words, replace each \"y\" with \"-x%2B38\". 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%2Bx-38=10\" Distribute the negative\r
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\n" ); document.write( "\n" ); document.write( "\"2x-38=10\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"2x=10%2B38\"Add 38 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"2x=48\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2848%29%2F%282%29\" Divide both sides by 2 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=24\" 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=24\"\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"x=24\" we can plug it into the equation \"y=-x%2B38\" (remember we previously solved for \"y\" in the first equation).\r
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\n" ); document.write( "\n" ); document.write( "\"y=-x%2B38\" Start with the equation where \"y\" was previously isolated.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-%2824%29%2B38\" Plug in \"x=24\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-24%2B38\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=14\" 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=14\"\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=24\" and \"y=14\"\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( "So the two numbers are 24 and 14
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