A rock is thrown in the air from the edge of a seaside cliff. Its height in feet is represented by f(x) = –16(x^2 – 8x – 9), where x is the number of seconds since the rock was thrown. The height of the rock is 0 feet when it hits the water. How long does it take the rock to hit the water? How many seconds? A. 16 seconds
B. 8 seconds
C. 1 second
D. 9 seconds