Pat a thin layer of hamburger in the bottom of a baking dish. Slice potatoes for the second layer. Slice carrots for the third layer. Spread a can of cream of mushroom soup over the top of this. Repeat a layer of hamburger. Then potatoes and then the carrots. Pour a can of tomato soup over the top. Bake at 350 degrees for 2 or 2 1/2 hours.