Confused

Increasing interval =  where does graph rise???

Decreasing interval = where does the graph fall ???

Note that the intervals are stated along x.....but....we look at y to determine if the graph rises or falls

And we read the graph from left to right

First one : 

This graph never rises......

So....the decreasing interval  is  ( - inf, inf)

Second one

Increasing interval   = (-2, inf)     Note that when x > -2....the graph rises 

Decreasing interval = (-inf, - 2)   Note that when x < -2  .....the graph falls from (-inf, -2)

Third one

This graph never decreases.....we have a vertical asymptote at x = -2

So  it increases from (-inf, -2)   and  (-2, inf) 

Hope this is clear....