Graphing problem.

May 2010
4
0
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!
 

pickslides

MHF Helper
Sep 2008
5,237
1,625
Melbourne
This one? \(\displaystyle y = \frac{-4}{x-4}\)
 

skeeter

MHF Helper
Jun 2008
16,216
6,764
North Texas
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 ...
 

pickslides

MHF Helper
Sep 2008
5,237
1,625
Melbourne
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 2010
4
0
Ok thanks so much guys..
I got
D: x can't equal 4
R: y can't equal 0
Function

Is that right?