When looking at a rational function f(x)= (x-6)(x+3)(x+4)/ (x+6)(x-3)(x-4), Jamal and Angie have two different thoughts. Jamal says that the function is defined at x = 6, x = 3, and x = 4. Angie says that the function is undefined at those x values. Who is correct? Justify your reasoning.

Please keep the answer simply and 11th grade level.