20.
A soccer ball is kicked upward from the ground with a speed of 96 feet per second. Its height h, in feet, after t seconds is given by the equation h(t) = -16² +96t.
HCL many seconds will it take the soccer ball to reach its maximum height?

Respuesta :

Answer:

After 3 seconds

Step-by-step explanation:

Given

[tex]h(t) = -16t^2 + 96t[/tex]

Required

Seconds to attain maximum height

The maximum of a quadratic function [tex]y = ax^2 + bx + c[/tex] is calculated using:

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

So, we have:

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

Where:

[tex]a = -16[/tex] and [tex]b = 96[/tex]

So:

[tex]t = -\frac{96}{2 * -16}[/tex]

[tex]t = -\frac{96}{-32}[/tex]

Cancel out negatives

[tex]t = \frac{96}{32}[/tex]

[tex]t = 3[/tex]