Answer: Phyllis starts with $50 and Chen starts with $15.
Explanation:
Given: Phyllis and Chen are saving money to go to a football game.
Phyllis made a graph to show the total she has saved at the end of each week.
From the given graph , we can see that the y intercept of the graph =(50,0)
i.e Phyllis has $50 when he started saving.
Also, Chen wrote an equation to show the total, y, he has saved at the end of each week, x.

At x= 0, we get

Therefore, Chen has $15 when he started saving.