Question 966110
x-A=0 will be 0 if A=-x, or x=-A, and f(x) will be undefined at x=-A.
MEANING:  Your denominator is {{{x-5}}}.


x-B=0 means that x=B.  You wanted {{{-3-B=0}}}, because that is according to {{{f(-3)=0}}}, a zero or root of the function.
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{{{-3-B=0}}}
{{{-3=B}}}
The numerator is {{{x-(-3)=x+3}}}.