X-12 +5x=90
That’s the set up
Let me know if you need more help
I think using a computer software would be the best answer because it is then fair
9^3 is in exponential form
Answer:

Step-by-step explanation:
we know that
----> by supplementary angles (form a linear pair)
Solve for x
Combine like terms

subtract 99 both sides

Divide by 3 both sides

Answer:
easy
Step-by-step explanation:oklook