-18x_2+39x-20

It seems that you've provided an expression, but it's not clear what you would like me to do with it. The expression appears to be a polynomial in the form \(-18x_2 + 39x - 20\).

If you're looking to simplify, factor, or analyze it in some way, please let me know! Here are a few possible actions I can take:

1. Simplify or combine like terms (although there are no like terms to combine in this case).
2. Factor the expression.
3. Find the roots of the polynomial (solve for x).
4. Evaluate the expression for specific values of \(x\).
5. Graph the expression.

Please provide more details on what you're looking for!