0.9 will equal to [tex] \frac{9}{10} [/tex]
Anyhow ! Lets get to the steps!
[tex] \frac{9}{10} - r  \leq  ?[/tex]
[tex] \frac{9}{10} [/tex]
Now "r" will become a negative 
[tex] \frac{9}{10} - - r  \leq ?[/tex]
[tex] \frac{-r(10)}{10} [/tex]
[tex] \frac{10(r)+9}{10}  \leq 0[/tex]
 We have to multiply from each of your sides by the number 10
You  can even divide by the number 10 aswell
Back to the steps
[tex]r+ \frac{9}{10}  \leq  ?[/tex]
Subtract from this fraction [tex] \frac{9}{10} [/tex] to your sides 
This would be inequality [tex]r + .900  \leq ? [/tex]
[tex]r \ \textless \   -\frac{9}{10} [/tex] ← this should most likely be your answer 
[tex]Now, Good Luck[/tex]