-x -3y +4x - 9y +2

*Combine like terms.

-x+4x= 3x
-3y-9y= -12y 

-3x-12y+2

It is a theory  that implies no effect or relationship between phenomena. A null hypothesis is found popular because it can be tested and be found false. Therefore, implying a relationship between the observed data.

Simply deactivate.
Having a normal life without any social networks involved actually feels very satisfying. Finding yourself not stuck on Facebook, uploading statuses and photos, checking to see how many people liked it or not is quite relieving. Do it, and focus more on meeting new people out there and intriguing them, not the overloaded phony bandwagon.