Well generally when mixing strains is an experiment, unless someone has done those two specific strains before. If you're using dry yeast, I would rehydrate them together and pitch and see what happens. You'll either get a mix of the profiles of the two yeasts, or one will dominate the other. I don't see this being useful with dry yeast as there are so few types and styles that you're likely not going to get enough variation to notice much difference. With liquid yeast you'd be able to mix and match many different styles, but I would only use strains you're familiar with already so you know what to expect from each strain individually before they are combined.
With only 5 batches under your belt, I'd say hold off on trying this for now until you're further along. I don't mean to discourage experimentation, but I feel it's always better to learn and keep it simple until you're very comfortable with one style of beer or type of yeast and THEN start screwing around with changing things. Too many variables changed at one time means you don't know what affect each variable has by itself.