document.write( "Question 375011: Bill is 6 years older than Tom. Three years ago, Bill's age was four times Tom's age. What are the boys ages now? How do I write this in a single variable equation? I have tried \"+%28x+%2B+6%29-3+=+4%28x-3%29\" and \"a-3=4%28a-6%29-3\" I have gotten this wrong on two different quizzes, so I am curious what the correct answer is? \n" ); document.write( "
Algebra.Com's Answer #266713 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Let B = bill's age now, T = Tom's age now\r
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\n" ); document.write( "\n" ); document.write( "So Bill's age 3 yrs ago was \"B-3\" and Tom's age 3 yrs ago was \"T-3\" \r
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\n" ); document.write( "\n" ); document.write( "Since \"Bill is 6 years older than Tom\", we know that \"B=T%2B6\"\r
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\n" ); document.write( "\n" ); document.write( "Also, because \"Bill's age was four times Tom's age\", we know that \"B-3=4%28T-3%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"B-3=4%28T-3%29\" Start with the second equation.\r
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\n" ); document.write( "\n" ); document.write( "\"T%2B6-3=4%28T-3%29\" Plug in \"B=T%2B6\" (ie replace each 'B' with 'T+6'). So this would be the starting point of the single variable equation you're looking for.\r
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\n" ); document.write( "\n" ); document.write( "\"T%2B6-3=4T-12\" Distribute.\r
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\n" ); document.write( "\n" ); document.write( "\"3%2BT=4T-12\" Combine like terms on the left side.\r
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\n" ); document.write( "\n" ); document.write( "\"T=4T-12-3\" Subtract \"3\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"T-4T=-12-3\" Subtract \"4T\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-3T=-12-3\" Combine like terms on the left side.\r
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\n" ); document.write( "\n" ); document.write( "\"-3T=-15\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"T=%28-15%29%2F%28-3%29\" Divide both sides by \"-3\" to isolate \"T\".\r
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\n" ); document.write( "\n" ); document.write( "\"T=5\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So this means that Tom is 5 yrs old.\r
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\n" ); document.write( "\n" ); document.write( "Now plug this value into \"B=T%2B6\" to get \"B=5%2B6=11\". So \"B=11\" which means that Bill is 11 yrs old.\r
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\n" ); document.write( "\n" ); document.write( "Notice that 3 yrs ago, Bill was 11-3=8 yrs old and Tom was 5-3=2 years old. Also notice that 8 is 4 times 2.\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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