I have to graph -4/x-4 and then find the domain, range, and if it is a function or not. I know how to do the ones with 1 as the numerator, but not -4. I have to do this by hand by the way. Any help is greatly appreciated!

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- May 27th 2010, 03:00 PMnjnest214Graphing problem.
I have to graph -4/x-4 and then find the domain, range, and if it is a function or not. I know how to do the ones with 1 as the numerator, but not -4. I have to do this by hand by the way. Any help is greatly appreciated!

- May 27th 2010, 03:44 PMpickslides
This one? $\displaystyle y = \frac{-4}{x-4}$

- May 27th 2010, 03:56 PMnjnest214
Yea like that

- May 27th 2010, 04:21 PMskeeter
first graph the "parent" $\displaystyle y = \frac{1}{x-4}$ ... note that the $\displaystyle -4$ factor does two transformations to the parent graph.

1. reflect over the x-axis

2. vertical stretch by a factor of 4.

see the graphs below ... - May 27th 2010, 04:23 PMpickslides
The -4 in the numerator, '-' is a reflection in the x-axis with a dilation factor of 4.

To find the domain and range you need to determine the asymptotes.

This is where the relation is not defined. Do you know how to find that?

Hint: The denominator cannot be zero. - May 27th 2010, 04:46 PMnjnest214
Ok thanks so much guys..

I got

D: x can't equal 4

R: y can't equal 0

Function

Is that right? - May 27th 2010, 04:56 PMpickslides
- May 27th 2010, 04:59 PMnjnest214Quote:

Why? How did you conclude this?