The given expression is of the form y = mx + c where m is the slope which represents the rate of change and c is the constant
We are given y =-50x+100
Slope = m= -50
Rate of change , dollar of the bank account = -$50 (negative)
This can be interpreted as the balance of the account gets reduced by $50 each month
From the equation, in month 1, the balance = -50+100 = 50
In month 2, balance - 50*2 +100 = 0
In month 3, balance = -50*3+100 = -50
and so on. So as we can see the balance of the account gets reduced by 50 and hence the rate of change in the bank account = -$50