SOLUTION: Find all the numbers for which the rational expression is undefined. I got to the point that I rewrote the problem as: 7z+5 = 0 But, I'm stuck now. I know I should be abl

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Find all the numbers for which the rational expression is undefined. I got to the point that I rewrote the problem as: 7z+5 = 0 But, I'm stuck now. I know I should be abl      Log On


   

Question 127296: Find all the numbers for which the rational expression is undefined.
I got to the point that I rewrote the problem as:
7z+5 = 0
But, I'm stuck now. I know I should be able to solve for z at this point, but I keep getting the wrong answer. What could I be doing wrong? Did I set the problem up wrong to begin with?
Found 2 solutions by checkley71, jim_thompson5910:
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
7z+5=0
7z=-5
z=-5/7 answer. IF you got this far correctly.

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Well if we solve for z, we get...


7z%2B5=0 Start with the given equation



7z=0-5Subtract 5 from both sides


7z=-5 Combine like terms on the right side


z=%28-5%29%2F%287%29 Divide both sides by 7 to isolate z



z=-5%2F7 Reduce

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Answer:
So our answer is z=-5%2F7 (which is approximately z=-0.714285714285714 in decimal form)



However, it will help if you post the original problem to see where you went wrong