Which of the following statements is true about the functions f(x)=5x = 15 and g(x) = 1/5x-3
a.f(5) = g(5) because f(x) and g(x) are inverse functions
b.f(-5) and g(5) because f(x) and g(x) are inverse functions.
c.f(x) and g(x) are inverse functions because f(x) and g(x) have the same domain.
d.f(x) and g(x) are inverse functions because f(g)=x and g(f)=x
plzzz help me