Question 53906
I'm not sure what your directions are, so I'm going to simplify the expression.  If that's not what you need, let me know.  I am also going to assume that the numbers after the variables are exponents.  Again, if I'm wrong let me know and I'll edit my response.
{{{x^3-4x+7x^2+3+2x}}}
When you're simplifying, you combine like terms.  Like terms are the same exact variables, with the same exact exponents.
{{{x^3+7x^2+(-4+2)x+3}}}
{{{x^3+7x^2-2x+3}}}
Happy Calulating!!!