SOLUTION: State the domain of the following and provide a brief explanation f(x)=square root x+4

What is under a square root radical must never be negative,
To guarantee that, we set  greater than or equal 
to 0:


  

Now we draw a number line and graph the inequality :

----------@===========================>
-7 -6 -5 -4 -3 -2 -1  0  1  2  3  4  5 

In interval notation that is 

Now for an explanation, in case the above isn't sufficient,

let's draw the graph of 





Compare the domain on the number line above to the x-axis
on the graph of .  The domain is just the
"shadow" of the graph of  upon the x-axis.

Edwin
AnlytcPhil@aol.com