Answer :
[tex]p+9 <7 \\ \\p< 7-9\\ \\ p < -2 \\ \\ Answer: \ x \in(-\infty ,-2)[/tex]
1)You add 9 to both side; so you subtract 9 from nine which leaves you 0
2)you subtract 9 from the other side, because you have to do the same things to both sides. so you get 7-9. Which equals -2.
3) you're equation will look like : p<-2