SOLUTION: How to find Domain and Range of this function without using a graph: 4-2√x

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Question 822281: How to find Domain and Range of this function without using a graph:
4-2√x

Found 2 solutions by LinnW, Edwin McCravy:
Answer by LinnW(1048) About Me  (Show Source):
You can put this solution on YOUR website!
The domain is restricted to x greater than or equal to 0
since a negative value of x produces a negative square root.
The largest y value, or top of the range is 4-2sqrt%28x%29.
All values of y less than this are in the the range.

Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
        _
y = 4-2√x

x must be non-negative, so the least value x can
take on is 0; thus its domain is [0,oo)

The largest possible value of y is when the least
amount is subtracted from 4, which is when x=0, and 
y=4,

so the range is (-oo,4]

graph%28400%2C400%2C-3%2C10%2C-6%2C7%2C4-2sqrt%28x%29%29

Edwin