If f(x)=x−9f(x) = x - 9f(x)=x−9, what is the coordinate of the x-intercept of the graph of f(x)f(x)f(x)?
(0,−9)(0, -9)(0,−9)
(9,0)(9, 0)(9,0)
(0,9)(0, 9)(0,9)
(−9,0)(-9, 0)(−9,0)