SOLUTION: Find all the numbers not in the domain of the function F(x)=(x^2-25)/(x^2-6x-27)

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Question 956941: Find all the numbers not in the domain of the function
F(x)=(x^2-25)/(x^2-6x-27)
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
F%28x%29=%28x%5E2-25%29%2F%28x%5E2-6x-27%29 the domain will be all real numbers excluding those which make denominator %28x%5E2-6x-27%29 equal to zero and they are:
x%5E2-6x-27=0
x%5E2-9x%2B3x-27=0
%28x%5E2-9x%29%2B%283x-27%29=0
x%28x-9%29%2B3%28x-9%29=0
%28x%2B3%29%28x-9%29=0
so, %28x%2B3%29=0=> if x=-3 and %28x-9%29=0=> if x=9
then, domain is:
{ x element R : x%3C%3E-3 and x%3C%3E9 }