Which function has a vertex at (2, -9)? * fx) = -(x - 3)2
Of(x) = (x + 8)2
O fx) = (x - 5)(x + 1)
O f(x) = -(x - 1)(x - 5)

Ineed with number 6 , explain how to get 1978

Which expression is rational? 6. , square root two, square root 14, square root 49

Aculture started with 2,000 bacteria. after 8 hours, it grew to 2,400 bacteria. predict how many bacteria will be present after 19 hours . round your answer to the nearest whole number. p=ae^kt