Question

How do you find the excluded value of `3/(x-5)`?

Answer 1

I got `x=5`

Explanation:

You need to consider the value of `x` that makes your fraction impossible to be evaluated; the only option is when `x=5`. This is because you would get `1/0` that you cannot evaluate!
So, when you have a fraction with unknown in it (in the denominator) always set the denominator equal to zero, solve it as a normal equation and exclude the value(s) of the unknown you find.
For example, in your case:
1) take the denominator: `x-5`;
2) set it equal to zero: `x-5=0`;
3) solve the equation: `x=5`;
Now you can exclude the result, `x=5,` from the set of values you can use into your fraction.