It takes the diver 5 s to reach the water.
<h3>Quadratic equations</h3>
These are mathematical equations in which the highest power of the unknown is 2 and in factored form are written as f(x) = (x -a)(x - b)
Since the Olympic divers height in feet above the water can be modeled by the function f(x) = -2(x-5)(x+1), where x is the time in seconds after he begins the dive.
The diver reaches the top of the water when f(x) = 0.
So, equating f(x) to zero, we have
f(x) = 0
-2(x-5)(x+1) = 0
Dividing through by -2, we have
(x-5)(x+1) = 0
So, (x - 5) = 0 or (x + 1) = 0
x = 5 or x = -1
Since time cannot be negative, x = 5 s.
So, it takes the diver 5 s to reach the water.
Learn more about quadratic equations here:
brainly.com/question/24860429
