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Quadratic With A Difference (Posted on 2008-04-15)

Determine all possible integer pair(s) (C, D) that satisfy this equation:

C² - 3CD = C - D

See The Solution Submitted by K Sengupta

Rating: 5.0000 (1 votes)

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solution

| Comment 1 of 5

C^2-3CD=C-D --> 9C^2 - 27CD = 9C - 9D -->

9C^2 - 9C = 27CD - 9D --> (3C-2)(3C-1)-2 = 9D(3C-1) -->

9D = 3C-2 - 2/(3C-1)

Since D is an integer, 9D is also --> C=0 or 1 only -->

(0,0) and (1,0) only.

Posted by Dennis on 2008-04-15 11:28:11

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