Analysis of LTI System in Frequency Domain

Plot the pole-zero in z-plane and draw magnitude response (not to the scale) of the system described by difference equation. > $$y[ n] - 0.3y[ n - 1] + 0.2y[ n - 2] = x[ n] - 0.5x[ n - 1]$$

Define the difference equation with example.

The Poles of a system are located at: $0.45 \pm 0.77i$ and $2 \pm 0.7i$ and zeros at: $1.2 \pm 0.43i$. Plot the magnitude response of this system.