Unless otherwise stated, polynomial functions and absolute value functions have a domain of . In other words, you can let take on any value you like.

In interval notation, this domain is .

For the function , this is a linear function, which is a straight line infinitely long in both directions. So the range is also , or .

For the function , we first need to consider the .

The absolute value function "gobbles up" all negatives and turns them positive. Thus the range of is or .

Subtracting 7 gives a vertical translation of 7 units down.

So the range of is or .