Q4. Suppose the repayment loan from a bank is described or modelled as a discrete time system as y[n] = (1+R/12)y[n-1] - x[n], where the output y[n] is the balance payment of the loan, input x[n] is the amount of loan payment in the n-th month, R is the annual interest rate, and n is the monthly time index. The initial condition y[0] is the amount of loan that was contracted. Assume that x[n] = C, which is equal amount of monthly payment. (a) Find how much you will have outstanding after the first three months. Assume a loan amount of GHc6,000 was contracted at a monthly payment of GHc200 and interest rate of 12%. (b) Find how long it will take to pay the loan. Write a Matlab script to implement this.