document.write( "Question 201893: Please Help:
\n" ); document.write( "Find the sum of the first five terms of the geometric sequence.\r
\n" ); document.write( "\n" ); document.write( "a = 1, r = -3
\n" ); document.write( " A) 121
\n" ); document.write( " B) 61
\n" ); document.write( " C) -121
\n" ); document.write( " D) -61
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Algebra.Com's Answer #152153 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
The formula for the sum of the first \"n\" terms of any geometric sequence is \"S=%28a%28r%5En-1%29%29%2F%28r-1%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"S=%28a%28r%5En-1%29%29%2F%28r-1%29\" Start with the given formula\r
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\n" ); document.write( "\n" ); document.write( "\"S=%281%28%28-3%29%5E5-1%29%29%2F%28-3-1%29\" Plug in \"a=1\", \"r=-3\", and \"n=5\"\r
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\n" ); document.write( "\n" ); document.write( "\"S=%281%28-243-1%29%29%2F%28-3-1%29\" Raise -3 to the 5th power to get -243\r
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\n" ); document.write( "\n" ); document.write( "\"S=%281%28-244%29%29%2F%28-4%29\" Subtract\r
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\n" ); document.write( "\n" ); document.write( "\"S=%28-244%29%2F%28-4%29\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"S=61\" Divide\r
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\n" ); document.write( "\n" ); document.write( "So the sum of the first five terms is 61 which means that the answer is B)
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