Answer:
x = 83/3.
Step-by-step explanation:
12x + 8 + 84 = 15х +9
Solving for x:
8 + 84 - 9 = 15x - 12x
83 = 3x
[tex]x = \frac{83}{3}[/tex]
12x + 8 + 84 = 15x + 9