need help dont understand
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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