For this case we have the following variables:
t: time in seconds.
f (t): height as a function of time.
By the time Grace reaches the pool, the height is equal to zero.
We have the following table:
Time (t) (in seconds) Height f(t) (in meters)
     1                  25
     2                  20
     3                  15
     4                  0
We observe that the height is equal to zero after 4 seconds.
Equivalently:
[tex] f (4) = 0 [/tex]
Answer:
the following represents the x-intercept of f(t):
Grace reaches the swimming pool after 4 seconds
