Probably just look at it in the absence of any other instructions. I'm presuming that x3 means and so on so you have a very lovely little 3rd degree polynomial. Since there is no equation -- not an equals sign as far as the eye can see -- this cannot be solved, so I'm at a loss as to what you mean by "do" in your question.
By the way, if you wish to indicate something raised to a power, use the caret sign (Shift-6), like this x^3. We will understand that to mean . The way you did it is not quite as obvious what you mean.
