document.write( "Question 951201: WRITING RULES: Write the next term in the sequence. Then write a rule for the nth term.
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\n" ); document.write( "(I understand that the sequence is multiples of 5, but I don't understand how they got the negative for every other number) THANKS!! :D :3
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Algebra.Com's Answer #580856 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
The multiples of 5 can be represented by the expression \"5n\" where \"n\" is a whole number\r
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\n" ); document.write( "\n" ); document.write( "Ex: if \"n+=+2\", then \"5n+=+5%282%29+=+10\"\r
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\n" ); document.write( "\n" ); document.write( "How do we alternate the signs? We introduce the term \"%28-1%29%5En\". If n is even, then \"%28-1%29%5En=1\" (ie positive 1). If n is odd, then \"%28-1%29%5En=-1\". There are no other outcomes for this piece. So this is why \"%28-1%29%5En\" is the perfect thing to tack on to help alternate the signs.\r
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\n" ); document.write( "\n" ); document.write( "The nth term is \"%28-1%29%5En%2A%285n%29\". Notice how I am multiplying \"%28-1%29%5En\" by \"5n\"\r
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\n" ); document.write( "\n" ); document.write( "To confirm this, let's plug in n = 2 to get \"%28-1%29%5En%2A%285n%29+=+%28-1%29%5E2%2A%285%2A2%29+=+1%2A10+=+10\". \r
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\n" ); document.write( "\n" ); document.write( "Now let's plug in n = 3 to get \"%28-1%29%5En%2A%285n%29+=+%28-1%29%5E3%2A%285%2A3%29+=+-1%2A15+=+-15\". \r
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\n" ); document.write( "\n" ); document.write( "I'll let you check the others.\r
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\n" ); document.write( "\n" ); document.write( "The next term is -25 as I'm sure you've already figured that out. Let's use n = 5 to confirm\r
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\n" ); document.write( "\n" ); document.write( "\"%28-1%29%5En%2A%285n%29+=+%28-1%29%5E5%2A%285%2A5%29+=+-1%2A25+=+-25\". \r
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\n" ); document.write( "\n" ); document.write( "If you need more one-on-one help, email me at jim_thompson5910@hotmail.com. You can ask me a few more questions for free, but afterwards, I would charge you ($2 a problem to have steps shown or $1 a problem for answer only).\r
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\n" ); document.write( "\n" ); document.write( "Jim\r
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