Stray cats loved eating goldfish in the pond leaving 6 goldfish. Paige had raised 8 goldfish in the pond initially. How many goldfish disappeared?
Let's denote the number of goldfish that disappeared as $x$. 

We know that $x$ goldfish disappeared, and that $8-x$ goldfish remained. 

We also know that $x$ is equal to the difference between the number of goldfish that were initially in the pond and the number of goldfish that were in the pond after the cats ate them. 

That is, $x=8-6=2$. 

Therefore, 2 goldfish disappeared.