Your expression seems a little incomplete. It seems you mean to ask
[tex]2x-7+\left(-9x\right)+81=0[/tex]
So, I am solving the question based on this, which anyways will solve your query.
Answer:
Please check the explanation.
Step-by-step explanation:
Given the expression
[tex]2x-7+\left(-9x\right)+81=0[/tex]
[tex]\mathrm{Remove\:parentheses}:\quad \left(-a\right)=-a[/tex]
[tex]2x-7-9x+81=0[/tex]
[tex]\mathrm{Group\:like\:terms}[/tex]
[tex]2x-9x-7+81=0[/tex]
[tex]\mathrm{Add\:similar\:elements:}\:2x-9x=-7x[/tex]
[tex]-7x-7+81=0[/tex]
[tex]\mathrm{Add/Subtract\:the\:numbers:}\:-7+81=74[/tex]
[tex]-7x+74=0[/tex]
[tex]\mathrm{Subtract\:}74\mathrm{\:from\:both\:sides}[/tex]
[tex]-7x+74-74=0-74[/tex]
[tex]-7x=-74[/tex]
[tex]\mathrm{Divide\:both\:sides\:by\:}-7[/tex]
[tex]\frac{-7x}{-7}=\frac{-74}{-7}[/tex]
[tex]x=\frac{74}{7}[/tex]
Therefore, the answer is:
- [tex]x=\frac{74}{7}[/tex]
