interval notations: finding domain and range of f(x)= 1/x+4 +5

This stuff is making my head hurt, can anyone explain it?
Find the domain and range of  f(x)= 1/x+4 +5 .

Give the answer for these in INTERVAL NOTATION. For this problem, enter both using INTERVAL NOTATION. For help with the notation, consult the link help (inequalities).


 
a) What is the domain of f(x)?   
 

b) What is the range of f(x)?   



HINT FOR DOMAIN AND RANGE :

Algebraically: For which x is the fraction undefined? This will give you the domain. You can find the range by thinking about the terms: the \frac{1}{x + 4} term can never be zero; however it can be any other real number (think about why). This means that f(x) can never equal ...

Graphically: You should be able to find the domain, without seeing the graph of this function, but to find the range, it may be useful to use a graphing calculator to see what the function looks like (search "graphing calculator online" for web-based graphing calculators). Note, this is an exception to the "NO CALCULATOR" rule. In this class, you would NOT be expected to graph this function by hand, but if you were given a picture of it, you would be expected to answer questions about it, like stating its domain and range.