Answer:
[tex]\large\boxed{x\in(-\infty,\ 8)\ \cup\ (10,\ \infty)}[/tex]
Step-by-step explanation:
[tex]-3+9x>87\qquad\text{add 3 to both sides}\\\\9x>90\qquad\text{divide both sides by 9}\\\\\boxed{x>10}\to(1)\\\\-x-9>-17\qquad\text{add 9 to both sides}\\\\-x>-8\qquad\text{change the signs}\\\\\boxed{x<8}\to(2)\\\\\text{From (1) and (2) we have:}\\\\x>10\ or\ x<8\to x\in(-\infty,\ 8)\ \cup\ (10,\ \infty)[/tex]
