Posted by Katie on Friday, October 28, 2011 at 12:40pm.
find all numbers for which the rational expression is undefinded
8/8z+7
I think the expression is undefined for all real numbers

help  Steve, Friday, October 28, 2011 at 12:46pm
If the fraction is 8/(8z) + 7 you are right.
If it is 8/(8z+7) then the answer is different. 
help  Steve, Friday, October 28, 2011 at 12:47pm
Oops. If 8/(8z) + 7, then it is undefined only for z=0
In general, a rational expression is undefined where the denominator is zero. 
help  KATIE A, Friday, October 28, 2011 at 12:48pm
Thank you steve

help  Steve, Friday, October 28, 2011 at 12:53pm
My pleasure. Now, go forth and solve similar problems with confidence!

help  Katie, Friday, October 28, 2011 at 12:56pm
I will try my best