document.write( "Question 1141349: What is the missing term of the geometric sequence {45,_,1620}? \n" ); document.write( "

Algebra.Com's Answer #761892 by Edwin McCravy(20059) $\"\"$ $\"About$

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The second term is the first term, 45, times r, the common ratio.  \r\n" );
document.write( "So the second term must be 45r.  So the sequence is\r\n" );
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document.write( "45, 45r, 1620\r\n" );
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document.write( "The third term is the second term, 45r, times r, the common ratio.  So the third term must be 45r².  But it's also 1620.\r\n" );
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document.write( "So we have the equation:\r\n" );
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document.write( "Divide both sides by 45\r\n" );
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document.write( "Take square roots of both sides:\r\n" );
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document.write( "So the second term 45r is 45(±6) or ±270.\r\n" );
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document.write( "The sequence is either\r\n" );
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document.write( "45, 270, 1620   or 45, -270, 1620.\r\n" );
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document.write( "Edwin

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