Can someone please help me with the matlab code of this question?

Identification of pole positions in a system Consider the system described by the difference equation y(n) = -ry(n 2) + x(n) (a) Let r = 0.9 and x(n) = 8(n). Generate the output sequence y(n) for 0 sns 127. Compute the N = 128-point DFT {Y(k)} and plot {\Y(k)|}. (b) Compute the N = 128-point DFT of the sequence w(n) = (0.92) -"y(n) where y(n) is the sequence generated in part (a). Plot the DFT values W(k)|. What can you conclude from the plots in parts (a) and (b)? (c) Let r=0.5 and repeat part (a). (d) Repeat part (b) for the sequence w(n) = (0.55) " y(n) where y(n) is the sequence generated in part (c). What can you conclude from the plots in parts (c) and (d)? (e) Now let the sequence generated in part (c) be corrupted by a sequence of mea- surement noise which is Gaussian with zero mean and variance o2 = 0.1. Repeat parts ) and (d) for the noise-corrupted signal