Question

PLEASE HELP

A ball is projected upward from the ground. Its distance in feet from the ground in t seconds is given by s(t) = - 16t2 + 122t. At what times will the ball be 213 feet from
the ground?

At ___second(s), the ball will be 213 feet from the ground.

Need to find the seconds.

Type an integer or decimal rounded to the nearest tenth as needed. Use a comma to separate answers as needed)

Answer 1

Answer:

• t = 2.7 seconds
• t = 4.9 seconds

Step-by-step explanation:

Given

Function

• s(t) = - 16t2 + 122t

To find

• Value of t when s(t) = 213

Solution

• 213 = -16t^2 + 122t
• 16t^2 - 122t + 213 = 0
• t = (122 ± √(-122)² -4*16*213)/2*16
• t = (61 ± √313)/16
• t = 2.7 seconds, t = 4.9 seconds