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Someone please help T.T I need help ASAP

Someone please help T.T I need help ASAP-example-1
User Colyn
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1 Answer

3 votes

Explanation:

Given that,

The quadratic equation that models the ball's height above the ground h, t seconds after it was thrown is given by :


h=-16t^2+108t+28 ...(1)

(a) For maximum height, put dh/dt = 0

So,


(d(h))/(dt)=(d)/(dt)(-16t^2+108t+28)=0\\\\-32t+108=0\\\\t=(108)/(32)=3.37\ s

Put the value of t in equation (1).

So,


h=-16(3.37)^2+108(3.37)+28\\\\h=210.24\ ft

(b) When the ball reaches the ground,

h = 0

So,


-16t^2+108t+28=0\\\\t=7\ s

So, the ball hits the ground in 7 seconds.

User Sucharu Hasija
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