SOLUTION: Can you help me with these problems? Find the domain and the range of these functions. 1. f(x)1/sqrt(5+x) 2. 3y-7x=15 Thank you so much!

Algebra ->  Functions -> SOLUTION: Can you help me with these problems? Find the domain and the range of these functions. 1. f(x)1/sqrt(5+x) 2. 3y-7x=15 Thank you so much!      Log On


   

Question 254781: Can you help me with these problems? Find the domain and the range of these functions.
1. f(x)1/sqrt(5+x)
2. 3y-7x=15
Thank you so much!
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Find the domain and the range of these functions.
1. f(x) = 1/sqrt(5+x)
Domain:
The denominator cannot be zero
and 5+x cannot be negative
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Solve 5+x > 0
x > -5
---
The domain is "All Real Numbers greater than 5".
---
Range:
Since sqrt(5+x)>0, f(x)> 0
----
The range is "All Real Numbers greater than 0.
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Graph the equation to see the range:
graph%28400%2C300%2C-10%2C10%2C-10%2C20%2C1%2Fsqrt%285%2Bx%29%29
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2. 3y-7x=15
y = (7/3)x + 5
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Its a line with non-zero slope that is not undefined.
Domain and Range are both "All Real Numbers".
graph%28400%2C300%2C-10%2C10%2C-10%2C10%2C%287%2F3%29x%2B5%29
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Cheers,
Stan H.