I have a little problem. I have to solve this task but I can't. 

> Z-transform of sequence $\{x(k)\}$ describe by the formula:
> 
> $$X(z) = \frac{2.5 -3.15z^{-1} + 1.2 z^{-2}}{1-2.3z^{-1} + 1.2z^{-2}}$$
> 
> Calculate of samples $x(-2), x(-1), x(0), x(1)$ and $x(2)$
> double-sides sequence, which correspond this Z-transform.

Thank you very much.

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"Double-side" sequence I mean sequence like this:

[![enter image description here][1]][1]
[![enter image description here][2]][2]
[![enter image description here][3]][3]

And I'm trying to solve this task with MatLab, I've used function "iztrans()" (inverse z-transformation) and I've gotten this results (below MatLab code and results):

[![enter image description here][4]][4]
[![enter image description here][5]][5]

But sequence which I've gotten isn't correct. Could you say what is my mistake?


  [1]: https://i.sstatic.net/8sEtJ.png
  [2]: https://i.sstatic.net/mPfhO.png
  [3]: https://i.sstatic.net/6YCN3.png
  [4]: https://i.sstatic.net/sYF7s.png
  [5]: https://i.sstatic.net/JQ3NS.png