Answer:
[tex]\large\boxed{x>9\to x\in(9;\ \infty)}[/tex]
Step-by-step explanation:
[tex]45 - 9.9x<-4.9x\qquad\text{add 9.9x to both sides}\\\\45<5x\qquad\text{divide both sides by 5}\\\\9<x\to x>9[/tex]
