For the next Olympic Winter Games, the organizers wish to expand the number of teams competing in curling. They wish to have 14 teams enter, divided into two pools of seven teams each. Right now, they’re thinking of requiring that in preliminary play each team will play seven games against distinct opponents. Five of the opponents will come from their own pool and two of the opponents will come from the other pool. They’re having trouble setting up such a schedule, so they’ve come to you. By using an appropriate graph-theoretic model, either argue that they cannot use their current plan or devise a way for them to do so.
I'm stuck on the way to draw the graphs. I have graph drawn to fit one pool, however I'm not sure how to show the opponents of the second pool.
Hint: Look at the graph of a single pool first. There are $7$ nodes, one for each team, and an edge drawn between them if they are playing. Each node has degree $5$.