SOLUTION: For what value(s) of y is this expression not defined? {{{(2y+1)/(y^2-y-6)}}}

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Question 310146:
For what value(s) of y is this expression not defined?
%282y%2B1%29%2F%28y%5E2-y-6%29

Answer by Edwin McCravy(20064) About Me  (Show Source):
You can put this solution on YOUR website!
For what value(s) of y is this expression not defined?

%282y%2B1%29%2F%28y%5E2-y-6%29 

We factor the denominator:

%282y%2B1%29%2F%28%28y-3%29%28y%2B2%29%29

We know that an expression is NOT defined for any value 
of the variable for which the denominator equals 0.
Therefore we set the denominator equal to 0, like this

%28y-3%29%28y%2B2%29=0

We now use the zero-factor property. 

Setting the first factor = 0,

y-3=0
y=3

Setting the second factor = 0,

y%2B2=0
y=-2

So the expression is not defined for the values 3 or -2.

Edwin