Question

If f(x)=20, what does x equal?

Answer 1

20

Explanation:

`X=20` because f (20) would also be 20. Since we don't know the value behind 20, we would suppose x is the value. The original equation is now
`f(x)=x`. If we do
`f(20)=x` we would get that (since x is being substituted)
`f(20)=20`.