An icicle drips at a rate that can be represented by the function f(x) = −x2 + 11x − 18, where 0 ≤ x ≤ 10 and x is the number of hours after the sun has risen. when f(x) is a negative number, the icicle is not dripping. determine the values when the icicle starts and stops dripping. x = 2 and x = 9 x = −2 and x = 9 x = 2 and x = −9 x = −2 and x = −9