That is just absolute value, basically what it means is take off whatever sign there was attached to it (such as a negative sign)
Answer:

Step-by-step explanation:
Given that,
The radius of cylinder, r = 1/6 inch
The height of the cylinder, h = 5/7 inch
We need to find the volume of the cylinder. The formula for the volume of a cylinder is given by :

So, the volume of the cylinder is equal to
.
I believe that -15 is the answer
The answer for 12 is x>3
The answer for 14 is z<-3