Question

2X to the third power minus 3X to the second power plus 9X X=-8

Answer 1

What is that 9X X near the end ??

I will assume you meant:
2x^3 - 3x^2 + 9x = -8
2x^3 - 3x^2 + 9x + 8 = 0
ran this through Wolfram and got this
https://www.wolframalpha.com/input/?i=solve+2x%5E3+-+3x%5E2+%2B+9x+%2B+8+%3D+0

Somehow don't think my interpretation is correct.
Retype your problem.