Answer :
[tex]0.3(0.3x+0.8)<-0.3\ /:0.3\\\\0.3(0.3x+0.8):0.3<-0.3:0.3\\\\0.3x+0.8<-1\\\\0.3x<-1-0.8\\\\0.3x<-1.8\ /:0.3\\\\x<- \frac{1.8}{0.3} \\\\x<- \frac{18}{3} \\\\x<-6\ \ \ \ \Leftrightarrow\ \ \ x\in(-\infty;\ -6)[/tex]
