SOLUTION: If my cat is 10 and I am 5 years older than my cat when will I be twice my cats age?

You are 15.  Five years ago you were 10 and your cat was 5. That's the only
time you were twice as old as your cat.  Now you are only 1.5 times as old
as your cat.  When you are 25 and your cat is 20 you will be only 1.25 times
as old as your cat.  As any two people (or animals) get older the ratio
of the older to the smaller decreases and gets closer and closer to 1.

So to answer your question, you never will again ever be twice as old as
your cat.  You were 5 years ago, but never again.

Edwin