Answer: C
Step-by-step explanation:
[tex]50 < 5x-10\\\\60 < 5x\\\\x < 12[/tex]
However, the angle has to have positive measure, so:
[tex]5x-10 > 0\\ \\ 5x > 10\\\\x > 2\\\\\therefore \boxed{2 < x < 12}[/tex]