contestada

A dolphin jumps out of the water with
an initial velocity of 20 feet per second.
The dolphin's height, h, after t seconds
of time can be modeled by the
equation:
h(t) = -16t2 + 20t.
Determine how long it took for the
dolphin to return to the water.

Respuesta :

calculista

Answer:

[tex]t=1.25\ sec[/tex]

Step-by-step explanation:

we have

[tex]h(t)=-16t^{2}+20t[/tex]

where

t is the time in seconds

h is the dolphin's height in feet

we know that

When the dolphin return to the water the value of h(t) is equal to zero

so

For h(t)=0

[tex]0=-16t^{2}+20t[/tex]

[tex]16t^{2}=20t[/tex]

Simplify

[tex]16t=20[/tex]

[tex]t=\frac{20}{16}[/tex]

[tex]t=\frac{5}{4}=1.25\ sec[/tex]

see the attached figure to better understand the problem

Ver imagen calculista

Otras preguntas