Answer:
y = Ax - 4
Explanation:
Given that:
Amount of money in account = y
Per week, x
Amount added to account per week is the same
Balance in account prior to saving = initial balance = - $4
The balance in Sandra's account :
y = (amount per week * number of weeks) + initial balance
Since the amount added per week is the same, then it can be represented as a constant, A
Hence, the function becomes ;
y = Ax + (-4)
y = Ax - 4