Final answer:
The Danube River enters Lake Constance and flows out at the Swiss-German Border, along with the Rhine River.
Step-by-step explanation:
The rivers that enter Lake Constance and flow out at the Swiss-German Border are the Danube River and the Rhine River.
The Danube River flows into Lake Constance from the south, while the Rhine River flows out of Lake Constance towards the north into Germany. These rivers are important waterways in Europe and have played a significant role in transportation and trade throughout history.