What is the domain and range of the equation below?

Question

anonymous · Answer

$$y=\sqrt{x-4}$$

raden · Answer

i think the domain of that function if x-4 >=0

anonymous · Answer

thats correct

anonymous · Answer

Can you write that answer more clearly? I don't understand what it means

anonymous · Answer

domains are determined where the function is defined
A function is undefined at places where the function is not:
1. divided by zero
2. square root of a negative number
3. log of less than 0

so where is this function defined or where the piece under the radical positive?

anonymous · Answer

sorry a function is undefined at places where the function IS:
*not "is not"

anonymous · Answer

So do you mean to say the domain is $$x \ge4$$

anonymous · Answer

in your case the number under the radical is defined for x >= 4, yes that is exactly right

anonymous · Answer

And what would the range be?

anonymous · Answer

for that you look at what the y values will be for the domain. 
here if x is less than 4, there is no real y value
when x = 4, y = 0
and as x gets larger y gets larger so the range is y >= 0

anonymous · Answer

Thank you.

anonymous · Answer

you're welcome