SOLUTION: find all numbers for which the following rational expression is undefined. If the rational expression is defined for all real numbers, state so. 5/(z-4)(z+2)

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Question 1002172: find all numbers for which the following rational expression is undefined. If the rational expression is defined for all real numbers, state so.
5/(z-4)(z+2)
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

5%2F%28z-4%29%28z%2B2%29
Rational expressions are undefined when the denominator is equal to 0. Since the denominator is equal to %28z-4%29%28z%2B2%29, make it equal to 0 and solve for z.
%28z-4%29%28z%2B2%29=0
if %28z-4%29=0=>z=4
if %28z%2B2%29=0=>z=-2
the rational expression is defined for all real numbers excluding z=4 and z=-2