find all numbers for which the rational expression is undefinded

8/8z+7

I think the expression is undefined for all real numbers

5 answers

If the fraction is 8/(8z) + 7 you are right.

If it is 8/(8z+7) then the answer is different.
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.
Thank you steve
My pleasure. Now, go forth and solve similar problems with confidence!
I will try my best