For $(x,y)$, positive integers, let $10xy+14x+15y=166$. Find $x+y$.
10xy + 14x + 15y = 166 simplify as
5y ( 2x + 3) = 166 - 14x
Since the left side is divisible by 5, then so is the right side
When x = 4
5y (2*4 + 3) = 166 - 14 * 4
5y (11) = 166 - 56
55y = 110
y = 2
So x + y = 4 + 2 = 6
Never seen a problem like this before.
Well done!
THANKS CPHILL :DDDD
+166 
