Part A:
Given that Martha can complete 15 activities a day at summer camp and she can choose between crafts or sports.
Let x be the number of crafts activity Martha did and let y be the number of sports activity Martha did.
The equation representing the situation is given by
x + y = 15
Part B:
There are many possible combinations of crafts and sports that Martha can do.
3 possible combinations of crafts and sports that Martha can do are
7 crafts and 8 sports
4 crafts and 11 sports
8 crafts and 7 sports