document.write( "Question 339832: If b and c are positive numbers and 1/b = b/c = c/8 then b+c = \r
\n" ); document.write( "\n" ); document.write( "(A)4
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\n" ); document.write( "\n" ); document.write( "Could please help me with the above problem\r
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Algebra.Com's Answer #243620 by Edwin McCravy(20055) $\"\"$ $\"About$

You can put this solution on YOUR website!
If b and c are positive numbers and 1/b = b/c = c/8 then b+c = ?
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document.write( "1/b = b/c = c/8 \r\n" );
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document.write( "Multiply all three sides by 8bc\r\n" );
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document.write( "8c = 8b² = bc²\r\n" );
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document.write( "Dividing 8c = 8b² through by 8 gives\r\n" );
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document.write( "c = b² \r\n" );
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document.write( "Dividing 8c = bc² through by c gives\r\n" );
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document.write( "8 = bc\r\n" );
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document.write( "So we have the system of equations:\r\n" );
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document.write( "c = b² \r\n" );
document.write( "8 = bc\r\n" );
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document.write( "Substituting b² for c in 8=bc\r\n" );
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document.write( "8 = b(b²)\r\n" );
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document.write( "8 = b³\r\n" );
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document.write( "2 = b\r\n" );
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document.write( "Substituting in \r\n" );
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document.write( "c = b² = 2² = 4\r\n" );
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document.write( "So,\r\n" );
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document.write( "b + c = 2 + 4 = 6   \r\n" );
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document.write( "So the correct choice is b + c = 6, choice B\r\n" );
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document.write( "Check to see that\r\n" );
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document.write( "1/b = b/c = c/8\r\n" );
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document.write( "1/2 = 2/4 = 4/8\r\n" );
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document.write( "which is true. So it checks.   \r\n" );
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document.write( "Edwin

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