Respuesta :
Answer: Ana will hit the water after 3 seconds.
Step-by-step explanation:
The exercise gives you the following function which models Anna's height  above the water (in meters) after diving "x" seconds:
[tex]h(x)=-5(x+1)(x-3)[/tex]
You can rewrite the function with [tex]h(x)=y[/tex]:
[tex]y=-5(x+1)(x-3)[/tex]
In order to calculate the number of seconds Ana will hit the water after diving, the procedure is:
- Substitute [tex]y=0[/tex] into the function:
 [tex]0=-5(x+1)(x-3)[/tex]
- Solve for "x".
By the Zero Product Property, you know that if [tex]a* b = 0[/tex], then [tex]a=0[/tex] or [tex]b=0[/tex].
Then you get:
[tex]x=-1\ or\ x=3[/tex]
- Choose the positive value ([tex]x=3[/tex])
Then, Ana will hit the water after 3 seconds.