Calculus: Is f=g?

Question

f(x)= (x²-9x) / (x-9) g(x)=x

does f=g? please explain, I am very rusty on this!

Answer 1

f(x) = (x²-9x) / (x-9) can have the numerator factored into x(x-9)

f(x) = x(x-9)/(x-9) = x

g(x) = x

f(x) = g(x) except for when x = 9. f(9) is undefined and has a hole at that particular point.

Answer 2

f(x)=(x^2-9x)/(x-9)

f(x)=x(x-9)/(x-9)

f(x)=x

g(x)=x

f(x)=g(x)