SOLUTION: Please help! Find all the numbers for which the rational expression is undefined. 1 divided by 9z + 1

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Question 595530: Please help!
Find all the numbers for which the rational expression is undefined.
1 divided by 9z + 1

Answer by math-vortex(648) About Me  (Show Source):
You can put this solution on YOUR website!
Find all the numbers for which the rational expression is undefined.
1 divided by 9z + 1
Hi, there--
.
There are two ways a rational expression can be undefined. 1) you attempt to take the square root of a negative number, and 2) the denominator of your expression is zero.
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There are no square roots here, so we're good on number 1.
Now we need to find any values of z where 9z+1 is equal to 0.
9z%2B1=0
9z=-1
z=-%281%2F9%29
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This means that your expression is undefined when z = -1/9.
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Hope this helps! Feel free to email if you have questions.
.
Mrs.Figgy
math.in.the.vortex@gmail.com