The function f(x) = -x2 - 7x + 30 shows the relationship between the vertical distance of a diver from a pool's surface f(x), in feet, and the horizontal distance x, in feet, of a diver from the diving board. What is a zero of f(x), and what does it represent?

x = 10; the diver hits the water 10 feet away horizontally from the board.
x = 3; the diver hits the water 3 feet away horizontally from the board.
x = 10; the diver jumps in the pool at 10 feet per second.
x = 3; the diver jumps in the pool at 3 feet per second.

FAN AND MEDAL!!!

Question

The function f(x) = -x2 - 7x + 30 shows the relationship between the vertical distance of a diver from a pool's surface f(x), in feet, and the horizontal distance x, in feet, of a diver from the diving board. What is a zero of f(x), and what does it represent? 

 x = 10; the diver hits the water 10 feet away horizontally from the board.
 x = 3; the diver hits the water 3 feet away horizontally from the board.
 x = 10; the diver jumps in the pool at 10 feet per second.
 x = 3; the diver jumps in the pool at 3 feet per second.

FAN AND MEDAL!!!