Dr. Chen is organizing a number guessing game in his Math Pr

Dr. Chen is organizing a number guessing game in his Math Problem Solving class. Three smart students Adam, Ben and Wukong are the participants. They need to find two numbers $x$ and $y$, such that $1<x<y<10$. Dr. Chen gives the sum $x+y$ to Adam, the product $xy$ to Ben and the sum $x+y+xy$ to Wukong. The 3 students are asked to write down their answer if they know. But no one knows what $x$ and $y$ are. After knowing that no one knows the answer in the first round, all of the 3 students know the correct answer in the second round. What are these two numbers $x$ and $y$? Show your reasoning.