SOLUTION: Find all numbers for which the rational expression is not defined: 2x-7 / x^2+5x-24

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Question 837926: Find all numbers for which the rational expression is not defined:
2x-7 / x^2+5x-24

Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
First of all, please put numerators and denominators in parentheses. What you posted meant:
2x-7+%2F+x%5E2%2B5x-24
But I'm quite sure you intended:
(2x-7)/(x^2+5x-24) or %282x-7%29%2F%28x%5E2%2B5x-24%29

A rational expression is undefined when its denominator is zero. So the answer(s) to this problem will be the solutions of:
x%5E2%2B5x-24+=+0
Factoring we get:
(x+8)(x-3) = 0
From the Zero Product Property:
x+8 = 0 or x-3 = 0
Solving these we get:
x = -8 or x = 3

So the values of x that make the rational expression undefined are -8 and 3.