Answer:
The relationship between Amy's age, a, and her sister's age is that her sister is 7 years less than twice Amy's age. To represent this relationship, we can use the equation:
2a - 7 = sister's age
This equation shows that the sister's age is equal to twice Amy's age minus 7.
Alternatively, we can use the equation:
a + (2a - 7) = 41
This equation shows that the sum of Amy's age and her sister's age is 41.
The correct equation is number 2. a + (2a - 7) = 41