document.write( "Question 479613: If c = 18a + 24b, where a and b are positive integers, then c must be divisible by which of the following?\r
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Algebra.Com's Answer #328591 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( " 18a + 24b\r\n" );
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document.write( "by the distributive principle (used in reverse)\r\n" );
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document.write( "6(3a + 8b)\r\n" );
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document.write( "Therefore it must be divisible by 6\r\n" );
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document.write( "An easy counter-example for the others is when a = 1, and b = 1\r\n" );
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document.write( "c = 18a + 24b = 18(1) + 24(1) = 18 + 24 = 42 which is \r\n" );
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document.write( "not divisible by 4, 9, 12, or 72\r\n" );
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document.write( "Edwin
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