document.write( "Question 1157937: The sum of the first three terms in a GP is 38. Their product is 1728. Find the values of the three terms.\r
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Algebra.Com's Answer #780881 by MathTherapy(10552)\"\" \"About 
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\n" ); document.write( "The sum of the first three terms in a GP is 38. Their product is 1728. Find the values of the three terms.
\n" ); document.write( "My answer were 8 and 18. I want to confirm if it's correct and how will I find the values of the three terms with two solution of a and r
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SUM of the 3 terms: 
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document.write( "                    \"matrix%281%2C3%2C+a%5B1%5D%2C+%22=%22%2C+38%2F%281+%2B+r+%2B+r%5E2%29%29\" ------- eq (i) 
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document.write( "Product of the 3 terms: \"a%5B1%5D%28a%5B1%5Dr%29%28a%5B1%5Dr%5E2%29\", and so: \"matrix%281%2C3%2C+a%5B1%5D%5E3r%5E3%2C+%22=%22%2C+%221%2C728%22%29\" ======>    
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document.write( "                        \"matrix%281%2C3%2C+a%5B1%5D%2C+%22=%22%2C+12%2Fr%29\" --------- eq (ii)\r
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document.write( "We then get: \"matrix%281%2C3%2C+38%2F%281+%2B+r+%2B+r%5E2%29%2C+%22=%22%2C+12%2Fr%29\"
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document.write( "             \"matrix%281%2C3%2C+12%281+%2B+r+%2B+r%5E2%29%2C+%22=%22%2C+38r%29\" ------ Cross-multiplying
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document.write( "             \"matrix%281%2C3%2C+6%281+%2B+r+%2B+r%5E2%29%2C+%22=%22%2C+19r%29\" ------- Factoring out GCF, 2
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document.write( "             \"matrix%281%2C3%2C+6+%2B+6r+%2B+6r%5E2%2C+%22=%22%2C+19r%29\"
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document.write( "             \"matrix%281%2C3%2C+6r%5E2+%2B+6r++-++19r+%2B+6%2C+%22=%22%2C+0%29\" 
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document.write( "             \"matrix%281%2C3%2C+6r%5E2++-++13r+%2B+6%2C+%22=%22%2C+0%29\"
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document.write( "             \"matrix%281%2C3%2C+6r%5E2++-++9r++-++4r+%2B+6%2C+%22=%22%2C+0%29\"
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document.write( "             3r(2r  -  3)  -  2(2r  -  3) = 0
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document.write( "             (3r  -  2)(2r  -  3) = 0
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document.write( "             3r  -  2 = 0		OR		2r  -  3 = 0
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document.write( "             3r = 2		        OR	        2r = 3
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document.write( "             
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document.write( "\"matrix%281%2C3%2C+r%2C+%22=%22%2C+2%2F3%29\"
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document.write( "\"matrix%281%2C3%2C+a%5B1%5D%2C+%22=%22%2C+12%2Fr%29\"
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document.write( "Therefore, if r, or common ratio = \"2%2F3\", then \"a%5B1%5D\" or 1st term = 18
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document.write( "In this case, the 3 terms are: 
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document.write( "\"matrix%281%2C3%2C+r%2C+%22=%22%2C+3%2F2%29\"
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document.write( "\"matrix%281%2C3%2C+a%5B1%5D%2C+%22=%22%2C+12%2Fr%29\"
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document.write( "Therefore, if r, or common ratio = \"3%2F2\", then \"a%5B1%5D\" or 1st term = 8
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document.write( "In this case, the 3 terms are: 
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