SOLUTION: 3/(7z+5) Find all numbers for which the rational expression is undefined I can't remember how you do this, I think I have it at equaling -5/7 but I am unsure, cause I thought

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: 3/(7z+5) Find all numbers for which the rational expression is undefined I can't remember how you do this, I think I have it at equaling -5/7 but I am unsure, cause I thought      Log On


   

Question 211251: 3/(7z+5)
Find all numbers for which the rational expression is undefined
I can't remember how you do this, I think I have it at equaling -5/7 but I am unsure, cause I thought with these kinds of problems it always has more then one answer
Found 2 solutions by stanbon, Earlsdon:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
3/(7z+5)
Find all numbers for which the rational expression is undefined
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It might have two answers if the denominator is a quadratic.
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But yours has 7z+5 which cannot be zero.
So you solve it for zero:
7z+5=0
z = -5/7
That is the value z cannot have.
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Cheers,
Stan H.

Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Find all numbers for which:3%2F%287z%2B5%29 is undefined.
The expression is undefined for all values of z that will make the denominator equal to zero (division by zero is "undefined")
Set the denominator to zero and solve for z:
7z%2B5+=+0 Subtract 5 from both sides.
7z+=+-5 Divide both sides by 7.
highlight%28z+=+-5%2F7%29
Your answer is absolutely correct!