The equation for a projectile's height versus time is h(t)=-16t^2+Vt+h.

A tennis ball machine serves a ball vertically into the air from a height of 2 feet, with an initial speed of 120 feet per second. After how many seconds does the ball attain its maximum height.

Round to the nearest hundred.

Respuesta :

Answer:

3.75 seconds

Step-by-step explanation:

Given:

[tex]h(t)=-16t^2+Vt+h[/tex]

[tex]h=2[/tex]

[tex]V=180[/tex]

Plug in given info into formula:

[tex]h(t)=-16t^2+120t+2[/tex]

Find the x-coordinate of the vertex:

[tex]t=-\frac{b}{2a}[/tex]

[tex]t=-\frac{120}{2(-16)}[/tex]

[tex]t=-\frac{120}{-32}[/tex]

[tex]t=\frac{15}{4}[/tex]

[tex]t=3.75[/tex]