Question

find all numbers that must be excluded from the domain of the rational expression
9/x−6

Answer 1

You cannot divide by zero. So x-6 cannot be equal to zero. So this means that x can't be equal to 6 (since x-6=6-6=0).


So the domain is the set of all real numbers but x can't equal 6.

Answer 2

So how do i show work for that?

Answer 3

show that solving for x-6=0 gives you x=6. So basically if x=6, then x-6=0. This then would mean that you have to exclude x=6 from the domain.