Respuesta :

Answer:

2.65 sec , 118.85 feet

Step-by-step explanation:

Given a parabola in standard form

h(t) = at² + bt + c ( a ≠ 0 )

Then the maximum occurs when

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

h(t) = - 16t² + 84.8t + 6.49 ← is in standard form

with a = - 16, b = 84.8 , then

t = - [tex]\frac{84.8}{-32}[/tex] = 2.65 seconds

The ball reaches its maximum height at 2.65 seconds

Substitute t = 2.65 into h(t) for maximum height

h(2.65) = - 16(2.65)² + 84.8(2.65) + 6.49

            = - 16(7.0255) + 224.72 + 6.49

            = - 112.36 + 231.21

            = 118.85

The maximum height is 118.85 feet