Date: Sat, 13 Jan 2001 10:33:02 +0100 (MET)
From: Ivan Sovic
If you want a integer solutions, look at this:
1 1 1
--+--=--- /*7xy
x y 7
7y+7x=xy
7y+7x-xy=0
y(7-x)+7x=0
y(x-7)=7x
7x
y=----
x-7
7x-49+49
y=----------
x-7
49
y=7+ -------
x-7
49
y is integer if ----- is integer.
x-7
That is integer if x= -42, 0, 6, 8, 14 or 56.
1 1
It can't be 0, because then ---=---
y 0
is imposible.
Solutions are (56,8), (14,14), (8,56), (-42,6), (6,-42).
73354661