Simple...
you have: [tex] 2x^{2} -9x+16=6[/tex]
To even begin, set all terms to the left side and set the parabola equal to zero-->>
[tex] 2x^{2} -9x+10[/tex]
Now, you can factor!
What multiplies to 20 and adds to -9?
-5*-4=20
-5+-4=-9
Then, using the box method...
x=[tex] \frac{5}{2} ,2[/tex]
Thus, your answer.