document.write( "Question 122873: The sum of two numbers is 38. Their difference is 12. What are the two numbers? the answer is 2x=50 that is right \r
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Algebra.Com's Answer #90190 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
If \"The sum of two numbers is 38\", then the first equation is \"x%2By=38\"\r
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\n" ); document.write( "\n" ); document.write( "If \"Their difference is 12\", then the second equation is \"x-y=12\"\r
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\n" ); document.write( "\n" ); document.write( "So we have the system:\r
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\n" ); document.write( "\n" ); document.write( "\"system%28x%2By=38%2Cx-y=12%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( "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=12\" 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=12\" Distribute the negative\r
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\n" ); document.write( "\n" ); document.write( "\"2x-38=12\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"2x=12%2B38\"Add 38 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"2x=50\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2850%29%2F%282%29\" Divide both sides by 2 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=25\" 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=25\"\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"x=25\" 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=-%2825%29%2B38\" Plug in \"x=25\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-25%2B38\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=13\" 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=13\"\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( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So the two numbers are 25 and 13\r
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