Final answer:
The equation that can be used to model this situation is y = 2x.
Step-by-step explanation:
The equation that can be used to model this situation is y = 2x.
This equation represents a linear relationship between the number of weeks (x) and the number of members in the chess club (y).
Each week, the number of members increases by 2, so the coefficient of x is 2 in the equation y = 2x.