document.write( "Question 448476: Use the geometric mean to find the 7th term in a geometric sequence if the 6th term is 8 and the 8th term is 8 \n" ); document.write( "
Algebra.Com's Answer #308597 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "7th term = (6th term)*r\r\n" );
document.write( "8th term = (7th term)*r\r\n" );
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document.write( "a7 = a6*r\r\n" );
document.write( "a8 = a7*r\r\n" );
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document.write( "a7 = 8*r\r\n" );
document.write( "8 = a7*r\r\n" );
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document.write( "Substitute 8*r for a7 in the second equation:\r\n" );
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document.write( "8 = (8*r)*r\r\n" );
document.write( "8 = 8rČ\r\n" );
document.write( "Divide through by 8\r\n" );
document.write( " 1 = rČ\r\n" );
document.write( "rČ = 1\r\n" );
document.write( " r = ±1\r\n" );
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document.write( "So there are two solutions:\r\n" );
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document.write( "a7 = 8*(±1)\r\n" );
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document.write( "So a7 is either 8 or -8.\r\n" );
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document.write( "Maybe your teacher only wanted the positive solution.\r\n" );
document.write( "You'll have to ask.\r\n" );
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document.write( "Or maybe your teacher wanted you to just use the formula\r\n" );
document.write( "for the geometric mean:\r\n" );
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document.write( "\"geometric_mean_of_x_and_y+=+sqrt%28xy%29+=+sqrt%288%2A8%29=sqrt%288%5E2%29=8\"\r\n" );
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document.write( "You'll have to ask your teacher.\r\n" );
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document.write( "Edwin
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