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October 1, 2016
Posted by **Steven** on Wednesday, August 14, 2013 at 4:29am.

2x^2+3xy+y^2+2x+y+18=0?

- math -
**Steve**, Wednesday, August 14, 2013 at 5:07am2(x+1/2)^2 + (y+1/2)^2 + 3xy + 18 = 3/4

Obviously either x or y will be negative, since we need 3xy to be negative to wipe out all those other positive numbers.

I count 12 pairs:

(-18,18)

(-18,35)

(-10,11)

(-10,18)

(-8,10)

(-8,13)

(10,-17)

(10,-14)

(12,-22)

(12,-15)

(20,-39)

(20,-22)